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Post questions, tips, tricks, and suggestions here Date Title 3/10/2021 Use VBA code to add and remove a watermark on all pages in a Word document 3/5/2021 Graph the gamma function in C# 2/28/2021 Calculate the gamma function in C# 2/23/2021 Find rectangles defined by a side and aspect ratio in C# 2/12/2021 Zip files with the ZipFile class in C# 2/5/2021 Simulate a doubling betting strategy in C# 2/3/2021 Book Drawing: C++ All-in-One For Dummies, 4th Edition 1/28/2021 Easily save and restore CheckedListBox values in the Registry in C# 1/26/2021 Use k-means clustering to find clusters of data in C# 1/26/2021 Automatically set camera distance in WPF and C# 1/19/2021 Make numbered buttons in C# 12/1/2020 Enlarge a polygon that has colinear vertices in C# 11/19/2020 Use the mouse wheel to scale images while cropping them to a desired aspect ratio in C# 11/16/2020 Allow scrolling while making a hexagonal montage in C# 11/6/2020 Use XAML data binding to display an animated rectangle's location 10/31/2020 Print product signs in C# 10/26/2020 Display flash cards in C# 10/15/2020 Label images at the bottom in C# 10/11/2020 Split images into halves in C# 10/9/2020 Allow scrolling while making a diagonal picture montage in C# 9/30/2020 Find controls by name in WPF with C# 9/23/2020 Let the user scribble on a background image in C# 9/21/2020 Insert a table into a RichTextBox in C# 9/20/2020 Draw a radar chart in C# 9/17/2020 Revised: Graph world total COVID-19 cases, deaths, and recoveries in C# 9/16/2020 Create button images in WPF and C# 9/8/2020 Overlay parts of images in C# 9/7/2020 Brighten pixels in an image in C# 9/5/2020 Perform binary contrast enhancement more quickly in C# 9/2/2020 Save a RichTextBox image in C# 8/31/2020 Expand a ComboBox when the user presses Enter in C# 8/27/2020 Make a blended composite image in C# 8/19/2020 Crop scaled images to a desired aspect ratio in C# 8/15/2020 Colorize images in C# 8/6/2020 Test graphical transformations in C# 7/31/2020 Use VBA code to pick random cells from a filtered selection in an Excel workbook 7/31/2020 Make multi-image icons from files in C# 7/29/2020 Make multi-image icon files in C# 7/23/2020 Use command line arguments to open files in C# 7/21/2020 Make a digital clock in C# 7/20/2020 Draw LED-style letters in C# 7/19/2020 Use Microsoft Print to PDF to create a PDF file in C# 7/13/2020 Use menu commands with shortcuts to save and restore user-drawn polygons in C# and WPF 7/12/2020 Pingback: Code Project post "Clipping Plane in WPF 3D" 7/10/2020 Sprialize an image in C# 7/7/2020 Let the user edit polygons in WPF and C# 7/7/2020 Let the user draw a polygon in WPF and C# 7/6/2020 Fill a target area found by trilateration in C# 7/3/2020 Perform trilateration in C# 6/27/2020 Draw many circles that intersect two points in C# 6/22/2020 Connect two points with elliptical arcs in C# 6/20/2020 Connect two points with arcs of midpoint circles in C# 6/18/2020 Improve the program that displays COVID-19 data for US states in C# 6/13/2020 Use VBA to make a Gantt chart showing work schedules 6/9/2020 Create a Contain FillMode for filling polygons in C# 6/5/2020 Find the angle between two vectors in C# 6/1/2020 Crop scaled images to specific sizes in C# 5/31/2020 Create a schedule for a round robin tournament with home teams in C# 5/25/2020 Understand fill modes in C# 5/16/2020 Display COVID-19 data for US states in C# 5/14/2020 Make a random tree of generic TreeNode objects in C# 5/13/2020 Quick COVID-19 update 5/6/2020 Prevent "underlying connection was closed" errors in C# 5/3/2020 Graph world total COVID-19 cases, deaths, and recoveries in C# 4/30/2020 Understand bitwise operators in C# 4/27/2020 Make bitmap extension methods that resize bitmaps in C# 4/26/2020 Resize pictures in a directory to specific widths or heights in C# 4/23/2020 Use code to make a slideshow in C# and WPF 4/17/2020 Graph COVID-19 recoveries and deaths per resolution in C# 4/16/2020 Graph COVID-19 deaths and deaths per million in C# 4/13/2020 Graph COVID-19 cases per million in C# 4/11/2020 Align graphs of COVID-19 case data in C# 4/8/2020 Load a picture and manipulate pixels in WPF and C# 4/7/2020 Download and graph COVID-19 case data in C# 4/7/2020 Build a Windows process tree in C# 4/6/2020 Draw lines with gaps to show they are passing under other lines in C# 4/1/2020 Recommended Book on CD: "The Serpent of Venice" by Christopher Moore 3/31/2020 Animate maze solving, version 3 3/30/2020 Animate maze solving, version 2 3/26/2020 Quarantine Reading Suggestions 3/25/2020 Recommended Book on CD: "Fool" by Christopher Moore 3/25/2020 Animate maze solving, version 1 3/23/2020 Solve mazes in C# 3/22/2020 Make a simple program to analyze COVID-19 symptoms in C# 3/12/2020 Move and resize polygons in WPF and C# 3/10/2020 Move and resize multiple shapes in WPF and C# 3/7/2020 Draw a horizontal compass in C# 2/25/2020 Load enums at runtime to understand them and their attributes in C# 2/19/2020 Draw an image circle in C# 2/10/2020 Use the ColorMatrix and ImageAttributes classes to quickly modify image colors in C# 2/5/2020 Draw a rounded polygon in C# 1/30/2020 Use big toolstrip buttons in C# 1/27/2020 Rotate images to straighten them in C# 1/23/2020 Make a hexagonal montage of pictures in C# 1/20/2020 Find drawn characters under the mouse in C# 1/16/2020 Clip an image to a polygon in C# 1/9/2020 Build a polygon selector class in C# 1/5/2020 Arrange images on the corners of a polygon in C# 12/26/2019 Make an improved diagonal picture montage in C# 12/20/2019 Use VBA to randomize Excel selections 12/18/2019 Understand range areas in Excel VBA 12/13/2019 Let the user draw rotated skewed polygons in C# 12/8/2019 Let the user draw rotated polygons with right angles in C# 12/4/2019 Let the user save an image of a smooth curve in C# 11/28/2019 Use a sprite class to animate bouncing cats in C# 11/19/2019 Draw interlocked circles in C# 11/8/2019 Draw arc wedges in C# 11/4/2019 Make an Apollonian gasket filled with images in C# 10/27/2019 Draw an image spiral in C# 10/22/2019 Draw an improved heartagram in C# 10/18/2019 Draw a heartagram in C# 10/14/2019 Connect two line segments with a circular arc in C# 10/8/2019 Crop images to specific sizes in C# 10/5/2019 Draw on top of a background image in C# 10/2/2019 Make a Word document with one picture on each page in C# 9/28/2019 See which section is under the mouse in a sunburst chart in C# 9/25/2019 Let the user drag ListBox items in C# 9/23/2019 Let the user arrange ListBox items in C# 9/18/2019 Make a Pinterest-style diagonal picture montage in C# 9/8/2019 Study a fascinating color illusion in C# 9/3/2019 Print circles centered inside other closely packed circles in C# 8/30/2019 Change a DataGridView entry when the user double-clicks a cell in C# 8/28/2019 Flow words around drop caps in C# 8/19/2019 Flow words around obstacles for document layout in C# 8/17/2019 Flow blocks around obstacles for document layout in C# 8/4/2019 Serialize and deserialize multiple images in files in C# 7/31/2019 Serialize and deserialize multiple images in C# 7/29/2019 Let the user drag pictures in a picture list in C# 7/24/2019 Improve the picture list in C# 7/22/2019 Make a picture list in C# 7/18/2019 Draw text with colors reversed along a sine wave in C# 7/17/2019 Draw text with colors reversed along a diagonal line in C# 7/15/2019 Draw text with colors reversed in its upper and lower halves in C# 7/13/2019 Draw random rectangles in C# 7/10/2019 Save a bitmap showing user drawn line segments in C# 7/3/2019 Give an image an improved transparent background in C# 6/27/2019 Make an image with rounded corners and a transparent background in C# 6/26/2019 Add a watermark to all of the files in a directory in C# 6/23/2019 Center text above or below a line segment in C# 6/21/2019 Resize images in C# 6/18/2019 Combine image slices in C# 6/13/2019 Adjust an image's opacity in C# 6/11/2019 Find hexes a certain distance from a target hex in C# 6/10/2019 Let the user draw a polyline in WPF and C# 6/7/2019 Let the user draw, move, and modify an arc in C#, Part 2 6/6/2019 Let the user draw, move, and modify an arc in C#, Part 1 6/5/2019 See whether a point is above an arc in C# 6/2/2019 Make a pie slice drawing extension in WPF and C# 5/28/2019 Book Review: Mission Python: Code a Space Adventure Game! 5/26/2019 New Book: Essential Algorithms, Second Edition: A Practical Approach to Computer Algorithms Using Python and C# 5/20/2019 Make an intuitive extension method to draw an elliptical arc in WPF and C# 5/17/2019 Draw an elliptical arc in WPF and XAML 5/15/2019 Make drawing extension methods in WPF and C# 5/10/2019 Make an image containing shadowed text in WPF and C# 5/8/2019 "WPF 3d" is now available for Kindle 5/7/2019 New page: Favorite Books 5/6/2019 Use transparency when drawing with anti-aliasing in C# 5/1/2019 Graph equations while preserving aspect ratio in WPF and C# 5/1/2019 WPF 3d: Three-Dimensional Graphics with WPF and C# 4/30/2019 Graph equations entered by the user in WPF and C# 4/24/2019 Use XAML and code behind to draw and outline shapes with gradients in WPF and C# 4/22/2019 Let the user draw a smooth curve with WPF and C# 4/17/2019 Draw a smooth closed curve in WPF and C# 4/15/2019 Draw a smooth curve in WPF and C# 4/13/2019 Let the user draw a smooth curve in C# 3/29/2019 Delete files from multiple folders quickly and easily in C# 3/27/2019 Use sines and cosines to draw circles and ellipses in C# 3/26/2019 "WPF 3d" code is avialable on GitHub 3/22/2019 Calculate the great circle distance between two latitudes and longitudes in C# 3/15/2019 Load Excel records into a DataGridView in C# 3/13/2019 Make a picture with a transparent hole in it in C# 3/8/2019 Let the user zoom on a picture and draw in C# 2/17/2019 List strings with a particular style in a Microsoft Word document in C# 2/13/2019 Segmented Turning Helper, Version 3 1/31/2019 Make a Word document with multiple pages in C# 1/29/2019 Solve Geometric Problems with C# 1/24/2019 Pingback: Code Project post "Orbital Mechanics Introduction, Part 2" 1/24/2019 Quick notes on the recent Windows update 1/19/2019 Winners of the book drawing 1/17/2019 Why you should study algorithms (plus a free book drawing) 1/11/2019 Book Drawing: The Modern C# Challenge 1/10/2019 Save and restore lines drawn by a WPF line editor in C# 1/6/2019 Convert camel case into underscore case in C# 12/27/2018 Create sized oval images in C# 12/24/2018 Use WPF 3d techniques to draw a snowman with WPF and C# 12/20/2018 Pingback: Code Project post "Clipping Plane in WPF 3D" 12/13/2018 Create oval images in C# 12/8/2018 Draw a randomly colored Sierpinski pentagon in C# 12/1/2018 Let the user draw lines in C# 11/27/2018 Book review: Python for Kids: A Playful Introduction To Programming 11/26/2018 Use a standard Windows dialog to let the user select folders in C# 11/23/2018 Gary Beene's gbUnSnarl game 11/14/2018 Find happy numbers in C# 11/12/2018 UPDATED: Draw a hypotrochoid (Spirograph curve) in C# 11/8/2018 Draw words on a circle in WPF and C# 11/6/2018 Draw a hyperbolic spiral in C# 11/2/2018 Review posted: "The Modern C# Challenge" 11/1/2018 Draw a logarithmic spiral in C# 10/30/2018 Draw a filled spiral in C# 10/29/2018 New Book: The Modern C# Challenge 10/26/2018 Draw an Archimedes spiral in C# 10/22/2018 Make a custom component in C# 10/17/2018 Tile a board with randomly colored trominoes in C# 10/12/2018 Tile a board with colored trominoes in C# 10/9/2018 Tile a board with trominoes in C# 10/5/2018 Draw text wrapped to fit columns in C# 10/4/2018 Draw a randomly colored Sierpinski pentagon in C# 10/1/2018 Draw a colored Sierpinski pentagon in C# 9/30/2018 Initialize TextBox contents for the computer's locale in C# 9/26/2018 Use label controls to draw a simple labeled histogram in C# 9/24/2018 Draw a simple labeled histogram in C# 9/20/2018 Rename files after their modification dates in C# 9/17/2018 Find a Ducci sequence in C# 9/10/2018 Encode and decode Futurama's alienese in C# 9/5/2018 Separate glyphs in an image in C#, Part 2 9/3/2018 Separate glyphs in an image in C#, Part 1 8/26/2018 Videos vs Animated GIFs - Pros and Cons 8/23/2018 Graph points in WPF and C# 8/13/2018 Search files for target text in C# 8/9/2018 Write Console window output to multiple places in C# 8/7/2018 Redirect Console window output to a TextBox in C# 7/30/2018 Get a weather forecast from openweathermap.org in C# 7/27/2018 Draw rose curves in C# 7/23/2018 Find two sets where the median of one is the mean of the other and vice versa in C# 7/19/2018 Trim images in C# 7/16/2018 Find Mersenne primes in C# 7/12/2018 Display a progress bar with text in WPF and C# 7/10/2018 Convert between ragged arrays and two-dimensional arrays 7/6/2018 Perform image hashing in C# 6/25/2018 Use the automatic code converters at developerFusion to convert C# code into Visual Basic, Ruby, and Python 6/20/2018 Copy ListView data into an array in C# 6/19/2018 Draw the spiral of Theodorus in C# 6/15/2018 Add LINQ to autocomplete in C# 6/14/2018 Improve autocomplete suggestion in C# 6/13/2018 Suggest autocomplete words in C# 6/12/2018 Build an MRU list that uses project settings in C# 6/11/2018 Build an MRU list in C# 6/8/2018 Useful tools and links 6/7/2018 Get information about Windows shortcuts in C# 6/6/2018 List the shortcuts in the computer's network neighborhood in C# 6/5/2018 Tile a bitmap with a string in C# 6/4/2018 Color the solutions to the "Find the squares in C#" puzzle 6/1/2018 Solve the "Find the squares in C#" puzzle 5/31/2018 Puzzle: Find the squares in C# 5/30/2018 Save WriteableBitmap images in multiple formats in WPF and C# 5/29/2018 Easily save a WriteableBitmap in WPF and C# 5/25/2018 Easily manipulate pixels in WPF and C# 5/24/2018 Display team names for a round robin tournament in C# 5/23/2018 Save bitmap files in WPF and C# 5/22/2018 Draw different styles of "illuminated" text in C# 5/21/2018 Draw "illuminated" text in C# 5/17/2018 Merge directories in C# 5/16/2018 Use a FileSystemWatcher to build a spooler in C# 5/15/2018 Implement interfaces explicitly or implicitly in C# 5/14/2018 Understand ways to end case blocks in C# 5/10/2018 Use a password protected Access database in C# 5/9/2018 Generate a random password in C# 5/8/2018 Why Twitter recently wanted you to change your password 5/8/2018 Control a loop that uses floating-point values in C# 5/7/2018 Display locale-aware sample dates and currency values in C# 5/5/2018 Make locale-aware methods use a new culture at runtime in C# 5/4/2018 Use PLINQ to select prime numbers from an array in C# 5/3/2018 Use PLINQ to select even numbers from an array in C# 5/3/2018 Disable the charms gesture in Windows 8 (and learn a bit about user interface design) 5/2/2018 Make the user enter a password to use a program in C# 5/2/2018 Make a Shakespeare insult generator in C# 5/1/2018 Rearrange text and format it to initialize variables in C# 4/30/2018 Make extension methods that pick random items from arrays or lists in C# 4/27/2018 Draw a Pythagoras tree fractal in C# 4/26/2018 Perform set operations on enumerable lists in C# 4/25/2018 Draw a Sierpinski pentagon in C# 4/24/2018 The most popular posts at C# Helper over the last 12 months 4/24/2018 Determine whether two lists contain the same sequences of objects in different orders in C# 4/23/2018 Determine whether two lists contain the same sequence of objects in C# 4/23/2018 Draw ransom note text in a RichTextBox in C# 4/22/2018 Draw ransom note text in C# 4/19/2018 Find duplicate files in C#, Part 4 of 4 4/18/2018 Find duplicate files in C#, Part 3 of 4 4/17/2018 Find duplicate files in C#, Part 2 of 4 4/16/2018 Find duplicate files in C#, Part 1 of 4 4/15/2018 Write a CSV file from an array in C# 4/13/2018 Calculate hash codes for a file in C# 4/12/2018 Copy a directory hierarchy into the executable directory in C# 4/11/2018 Use an animated cursor in C# 4/6/2018 Display database pictures in a ListView control in C# 4/3/2018 Create ListView icons at run time in C# 4/2/2018 Use LINQ with an embedded lambda expression to find prime numbers in C# (Part 3 of 3) 3/31/2018 Use more efficient LINQ to find prime numbers in C# (Part 2 of 3) 3/30/2018 Use LINQ to find prime numbers in C# (Part 1 of 3) 3/29/2018 Draw a cursor and use it at run time in C# 3/28/2018 Let the user select the ScrollBar maximum in C# 3/27/2018 Fix rectangle SmoothingMode problems in C# 3/26/2018 Compress and decompress directories in C# 3/23/2018 Understand region directives in C# 3/22/2018 Disable Visual Studio warnings in C# 3/21/2018 Use XML literals in C# 3/20/2018 Use VBA macros to add hyperlinks to external files 3/19/2018 Display icons next to ListView sub-items in C# 3/16/2018 Display large and small ListView icons in C# 3/14/2018 Get assembly information in C# 3/13/2018 Use a custom dash pattern with WPF and XAML in C# 3/12/2018 Use StringFormat to align text in columns in C# 3/9/2018 Use tabs and StringFormat to align text in C# 3/8/2018 Make a skinned form in C#, Part 2 (the code) 3/6/2018 Make a skinned form in C#, Part 1 (the controls) 3/5/2018 Use VBA to randomize cells in Excel 3/2/2018 Make a PictureBox act like a button in C# 3/1/2018 See if the internet is available in C# 2/27/2018 Use reflection to list a class's events in C# 2/26/2018 Use reflection to list a class's methods in C# 2/23/2018 Use reflection to list the fields provided by the SystemInformation class in C# 2/22/2018 Use reflection to list a class's fields in C# 2/21/2018 Use reflection to list SystemInformation properties in C# 2/20/2018 Use reflection to list a class's properties in C# 2/19/2018 Copy files to the clipboard in C# 2/16/2018 Paste files from the clipboard in C# 2/15/2018 Display a horizontal scrollbar in a ListBox in C# 2/15/2018 How to use the examples at C# Helper 2/14/2018 Draw text on a circle in C# 2/13/2018 List Dictionary keys and values in C# 2/12/2018 Animate a point on a polar coordinate curve in C# 2/10/2018 Combine images in rows and columns in C# 2/9/2018 New Book: WPF 3d, Three-Dimensional Graphics with WPF and C# 2/9/2018 Book Sample Pictures: WPF 3d 2/9/2018 Book Errata Page: WPF 3d 2/9/2018 Book Discussion Page: WPF 3d 2/9/2018 WPF 3d: Table of Contents 2/9/2018 Graph a square curve in C# 2/8/2018 Graph a curve in polar coordinates in C# 2/7/2018 Create a PowerPoint presentation from a Word document in C# 2/6/2018 Compare floating-point values safely in C# 2/5/2018 Resize a RichTextBox to fit its contents in C# 2/4/2018 Blank the WebBrowser control in C# 2/2/2018 Make a scrolled window in C# 2/1/2018 Resize a TextBox to fit its text in C# 1/30/2018 Extract comments from a group of files in C# 1/26/2018 Justify paragraphs in C# 1/26/2018 Align text by lines in C# 1/25/2018 Draw paragraphs one line at a time in C# 1/24/2018 Print values in a grid in C# 1/23/2018 Use Word to make a PDF containing pictures in C# 1/22/2018 Make a Word document containing pictures in C# 1/19/2018 Quick tip: Use pinvoke.net to get information about API functions for use in C# 1/18/2018 Find Visual Studio's Immediate window 1/17/2018 Map device coordinates to world coordinates in C# 1/15/2018 How to send an SMS text message in C# 1/11/2018 Calculate credit payments in WPF and C# 1/10/2018 Extract part of a JSON file in C# 1/8/2018 Write a TreeView into a tab-delimited file in C# 1/4/2018 Use JSON to serialize and deserialize objects in C# 1/2/2018 Display tooltips on a graph of an equation entered by the user in C# 12/30/2017 Download and display a text file whenever a program starts in C# 12/30/2017 Anatomy of an example 12/24/2017 Make an owner-drawn ListBox that justifies columns in C# 12/22/2017 Draw aligned columns of data in C# 12/20/2017 Format values in a ListBox in C# 12/19/2017 Right-justify values in a ListBox in C# 12/18/2017 Delete files quickly and easily in C# 12/16/2017 Understand the startup form (or main form) in C# 12/15/2017 Find a form's screen in C# 12/14/2017 Position a form so it does not stick off the edge of the screen in C# 12/13/2017 Position a form over another form in C# 12/12/2017 Use Debug and Trace listeners in C# 12/11/2017 Use branch and bound to find the highest value path through a two-dimensional array of numbers in C# 12/8/2017 Find the highest value path through a two-dimensional array of numbers in C# 12/7/2017 Save Excel data in a PDF file in C# 12/6/2017 Load a cursor from a resource in C# 12/5/2017 Draw a Fibonacci word fractal in C# 11/29/2017 Calculate Fibonacci words in C# 11/28/2017 Use the Stopwatch class to time a program in C# 11/27/2017 Use the BigInteger structure in C# 11/22/2017 Make a context-sensitive AcceptButton in C# 11/21/2017 A little light holiday reading 11/21/2017 Initialize a TreeView control to display a directory hierarchy in C# 11/17/2017 Cast arrays from one reference type to another in C# 11/16/2017 Use a timer to make a form TopMost or BottomMost in C# 11/15/2017 Make a form TopMost or BottomMost in C# 11/14/2017 Make a StatusLabel display its text even if it doesn't fit in C# 11/13/2017 Generate letters with given frequencies in C# 11/10/2017 Make a text file a project resource in C# 11/9/2017 Make a class define and raise events in C# 11/8/2017 Use statement lambdas in C# 11/7/2017 Use lambda expressions in C# 11/6/2017 Use anonymous methods in C# 11/3/2017 Use the predefined Action, Func, and EventHandler delegate types in C# 11/1/2017 A quick note on error messages 11/1/2017 Make a button display the picture beneath slightly grayed it in C# 10/31/2017 Make a button display the picture beneath it in C# 10/30/2017 Validate optional parameters in C# 10/28/2017 Use named and optional parameters in C# 10/26/2017 Display system metrics with descriptions in C# 10/25/2017 Get system metrics in C# 10/24/2017 Convert an array of bytes into an integer and back in C# 10/23/2017 Make subarray extension methods in C# 10/19/2017 Use Array.Copy to copy values in two-dimensional arrays in C# 10/16/2017 Determine whether a year is a leap year in C# 10/14/2017 Get a hard drive serial number in C# 10/14/2017 Get a disk volume serial number in C# 10/12/2017 Find class ancestors in C# 10/11/2017 Find classes that implement an interface or that are descendants of a given class in C# 10/10/2017 Display subscripts and superscripts in a RichTextBox in C#, version 2 10/5/2017 List a program's loaded assemblies in C# 10/5/2017 Get the computer's registered owner and organization in C# 10/3/2017 Get the computer's operating system in C# 9/30/2017 Draw a picture-filled histogram in C# 9/28/2017 Write values in the Registry in C# 9/27/2017 Read Registry values (to get the desktop icon size) in C# 9/27/2017 Linkback to the Secret Santa Problem 9/26/2017 Define custom exception classes in C# 9/25/2017 See a hierarchy of exception classes for use in C# 9/23/2017 Throw a standard exception in C# 9/21/2017 Make a dice-rolling simulation in C# 9/20/2017 Tile a PictureBox in C# 9/14/2017 Use a symbiote to graphically select hours in C# 9/13/2017 Graphically select hours in C# 9/12/2017 Remove unnecessary using directives in C# 9/11/2017 Draw the Weierstrass function in C# 9/11/2017 Determine whether a file or directory exists in C# 9/8/2017 Calculate Fibonacci numbers in several ways in C# 9/7/2017 Recursively draw equations in C# 9/7/2017 The C# Helper Top 100 now available at Amazon 9/5/2017 Efficiently see if a string is blank in C# 9/4/2017 Table of Contents: The C# Helper Top 100 9/4/2017 New Book: The C# Helper Top 100 9/1/2017 Change image resolution in C# 8/30/2017 Examine the unique words in a Microsoft Word file in C# 8/29/2017 Find random prime numbers in C# 8/28/2017 Probabilistically determine whether a number is prime in C# 8/25/2017 Iterate over items in an array with unknown dimensions in C# 8/24/2017 Solution to puzzle: Zero rows and columns in an array in C# 8/23/2017 Draw improved text on a curve in C# 8/22/2017 Make a TextBox preview extender provider in C# 8/21/2017 Make the user enter a float in C# 8/19/2017 Preview TextBox changes in C#, Part 2 8/17/2017 Preview TextBox changes in C# 8/16/2017 Use Array methods in C# 8/15/2017 Puzzle: Zero rows and columns in an array in C# 8/14/2017 Compare performance looping over DateTime and integer variables in C# 8/11/2017 Find Friday the Thirteenths in C# 8/11/2017 Use == and != to compare structs in C# 8/10/2017 Book Review: Super Scratch Programming Adventure!: Learn to Program By Making Cool Games 8/9/2017 Animate rainbow colors in C# 8/8/2017 Animate exploding 3-dimensional pie slices in C# 8/7/2017 Use the mouse wheel to scale an image in C# 8/6/2017 Use Windows Forms controls to make multiple stacked expanders in C# 8/5/2017 Use Windows Forms controls to make an expander in C# 8/3/2017 Calculate where a line segment and an ellipse intersect in C# 8/2/2017 Make transparent button images in C# 8/1/2017 List USB devices in C# 7/27/2017 Draw "marching ants" dashed lines in C# 7/26/2017 Draw dashed lines that are visible on any background in C# 7/25/2017 Produce a repeatable series of "random" numbers in C# 7/22/2017 Safely manage documents in C# 7/21/2017 Get font size in pixels in C# 7/19/2017 Draw smooth text in a GraphicsPath in C# 7/15/2017 Create a class outside of any namespace statement in C# 7/15/2017 Book Review: The Manga Guide to Linear Algebra 7/12/2017 Get the screen's resolution in C# 7/8/2017 Make Ctrl+A select all of the text in a TextBox in C# 7/7/2017 Generate random polygons in C# 7/5/2017 Make extension methods to generate random double values in C# 7/3/2017 Iterate over the items in arrays and lists in C# 6/30/2017 Print a ListView control's contents on multiple pages in C# 6/27/2017 Update a DataTable that is bound to a DataGridView in C# 6/25/2017 Print a ListView with large contents in C# 6/22/2017 Print the contents of a ListView control in C# 6/21/2017 Make rectangle extension methods in C# 6/19/2017 Use string extension methods to validate Social Security numbers in C# 6/17/2017 Understand the @ symbol in C# 6/16/2017 Center a form on the screen at run time in C# 6/16/2017 Understand when a finally block is executed in C# 6/3/2017 Use a ProgressBar in C# 6/1/2017 Make pop buttons in C# 5/29/2017 Calculate the present value of a future amount of money in C# 5/27/2017 Make silly eyes that track the mouse without flicker in C# 5/26/2017 Make silly eyes that track the mouse in C# 5/26/2017 Compare the performance of simple arithmetic operations in C# 5/25/2017 Make a 3D globe in WPF and C# 5/25/2017 Graph event probabilities in C# 5/24/2017 Find the number of trials for an event probability in C# 5/23/2017 Calculate the probability of an event occurring in a given number of trials in C# 5/22/2017 Understand probabilities of unrelated events (and escaping zombies) 5/19/2017 Display reusable dialog forms in C# 5/18/2017 Make a TextBox with auto-complete in C# 5/17/2017 Compare the performance of the int, long, and byte data types in C# 5/16/2017 Compare the performance of the float, double, and decimal data types in C# 5/12/2017 Save several images into Access in C# 5/10/2017 Find .NET libraries for namespaces in C# 5/10/2017 Load images from an Access database in C# 5/9/2017 Save images in an Access database in C# 5/8/2017 Use the Filter property to select image files in C# 5/5/2017 Use filenames stored in a database to display images in C# 5/4/2017 Move and resize multiple rectangles in WPF and C# 5/3/2017 Display database records without data binding in C# 5/2/2017 Initialize lists from databases without binding in C# 5/1/2017 Check a TreeView subtree in C# 4/28/2017 Display context menus for TreeView items in C# 4/27/2017 Enumerate TreeView nodes in C# 4/26/2017 Yield checked TreeView nodes in C# 4/25/2017 Make a list of checked TreeView nodes in C# 4/24/2017 Display tooltips for TreeView nodes in C# 4/21/2017 Compare sorting algorithms in C#, part 5 of 5 (Countingsort) 4/21/2017 Compare sorting algorithms in C#, part 4 of 5 (Quicksort) 4/20/2017 Compare sorting algorithms in C#, part 3 of 5 (Selectionsort) 4/19/2017 Compare sorting algorithms in C#, part 2 of 5 (Bubblesort) 4/18/2017 Compare sorting algorithms in C#, part 1 of 5 (Array.Sort) 4/14/2017 Run user-entered code that modifies the program's form in C# 4/13/2017 Use the yield statement in C# 4/12/2017 Understand AutoScaleMode in C# 4/11/2017 Draw transformed text in C# 4/11/2017 Tip: Make parentheses matching more visible in C# 4/10/2017 Display tips in a status bar instead of a tooltip in C# 4/7/2017 Make a sunburst chart in C#, Part 4 4/6/2017 Make a sunburst chart in C#, Part 3 4/5/2017 Make a sunburst chart in C#, Part 2 4/4/2017 Make a sunburst chart in C#, Part 1 4/3/2017 Make a status strip label that sticks to the right side of the form in C# 3/31/2017 Parse file sizes in KB, MB, GB, and so forth in C# 3/30/2017 Highlight the DataGridView row that is under the mouse in C# 3/29/2017 Use accelerators on labels and buttons in C# 3/28/2017 Compare the performance of incrementing statements in C# 3/27/2017 Make a simple event logger in C# 3/25/2017 Display a form's control hierarchy in C# 3/23/2017 Loop over a form's controls in C# 3/22/2017 Make a shaded ellipse control in C# 3/21/2017 Quickly insert standard menu items on a form in C# 3/20/2017 Give a class default indexer properties in C# 3/17/2017 Solution: The 40 pound stone puzzle 3/16/2017 Activate another running program in C# 3/15/2017 Use digits of Pi to draw a picture in C# 3/15/2017 Look for dates in the digits of Pi in C# 3/14/2017 Find patterns within Pi in C# 3/14/2017 Puzzle: The 40 pound stone 3/13/2017 Make the basis for a card game in C# 3/13/2017 Verify sizes of playing cards in C# 3/10/2017 Use System.Threading.Timer to make a countdown timer in C# 3/8/2017 Installing Visual Studio 2017 3/8/2017 Use an improved extension method to calculate standard deviation in C# 3/7/2017 Remove a TextBox control's context menu in C# 3/6/2017 Use ActiveControl to enabled and disable menu items in C# 3/2/2017 Use the ActiveControl property in C# 3/1/2017 Make a case-insensitive dictionary in C# 2/28/2017 Understand string equality testing in C# 2/27/2017 Use a Dictionary to store and retrieve items in C# 2/25/2017 Compare the performance of string comparison methods in C# 2/24/2017 Compare the performance of switch and if statements in C# 2/23/2017 Draw, move, and delete line segments in VB.NET 2/21/2017 Convert a Rectangle into a RectangleF and vice versa in C# 2/20/2017 Make a hangman game in C# 2/16/2017 Use LINQ to select words of certain lengths from a file in C# 2/15/2017 Draw a golden spiral in C# 2/14/2017 Draw a nested series of golden rectangles in C# 2/13/2017 Examine the relationship between the Fibonacci sequence and phi in C# 2/11/2017 Use a TextFieldParser to read fixed-width data in C# 2/10/2017 Use a TextFieldParser to read delimited data in C# 2/8/2017 Suspend or hibernate the system in C# 2/7/2017 Make light pixels transparent in an image in C# 2/6/2017 Draw a smiley face with WPF in C# 2/3/2017 Rotate images that are scaled in C# 2/2/2017 Rotate images inside a scrolled panel in C# 2/1/2017 Explore the Visual Studio Image Library in C# 1/31/2017 List controls on a form in C# 1/30/2017 Give transparent backgrounds to images displayed on buttons in C# 1/26/2017 Easily draw rotated text on a form in C# 1/25/2017 Display the Astronomy Picture of the Day on the desktop in C# 1/24/2017 Download the Astronomy Picture of the Day in C# 1/23/2017 Randomly change the desktop picture in C# 1/20/2017 Set the Windows desktop picture in C# 1/19/2017 Convert RTF and TXT files into DOCX files in C# 1/17/2017 Draw a scrolling family tree in C# 1/17/2017 Remove non-printable ASCII characters from a string in C# 1/16/2017 See what processes have a file locked in C# 1/13/2017 Use "banker's rounding" and "normal rounding" in C# 1/12/2017 See if a file is locked in C# 1/11/2017 Map between host names and IP addresses in C# 1/10/2017 List available culture codes in C# 1/9/2017 Make a cannon game in C# 1/6/2017 Convert a bitmap into a cursor in C# 1/5/2017 Use a bitmap for an icon in C# 1/4/2017 Make a tool that creates PNG files with transparent backgrounds in C# 1/3/2017 Give an image a transparent background in C# 1/2/2017 Make a TextBox convert text into proper case in C# 12/31/2016 Five hats puzzle solution 12/31/2016 Five hats puzzle 12/30/2016 Convert a string to proper case (title case) in C# 12/29/2016 Make TextBoxes automatically convert case in C# 12/28/2016 See if Internet Explorer uses a proxy in C# 12/27/2016 Move a window with a title that matches a pattern in C# 12/26/2016 Tile desktop windows in rows and columns in C# 12/23/2016 Set another application's size and position in C# 12/23/2016 Find a target window and minimize, maximize, or restore it in C# 12/23/2016 Make a stopwatch in C# 12/21/2016 Extract text from a metafile in C# 12/21/2016 Enumerate the records in a metafile in C# 12/20/2016 Draw an interesting pattern of circles in C# 12/19/2016 Use BeginInvoke and callbacks to perform tasks asynchronously in C# 12/16/2016 Use BeginInvoke and EndInvoke to perform tasks asynchronously in C# 12/15/2016 Use base insets with custom end caps in C# 12/14/2016 Hints for beginners without sacrificing efficiency 12/14/2016 The ribbon interface: sacrificing usability for discoverability 12/13/2016 Loop over an array of unknown dimension in C# 12/13/2016 Loop over entries in an array of unknown length in C# 12/12/2016 Display memory usage in C# 12/11/2016 Sort ListView controls by all columns or clicked columns in C# 12/10/2016 Add "extension properties" to classes in C# 12/9/2016 Apply a color threshold to an image in C# 12/9/2016 Adjust image translucency in C# 12/8/2016 Provide gamma correction for an image in C# 12/7/2016 Make stable appointments in C# 12/6/2016 Display thumbnails for image files in a directory in C# 12/5/2016 Update to "Interview Puzzles Dissected" sample puzzles 12/5/2016 Draw outline graphics in C# 12/2/2016 Graph currency rates over time in C# 12/2/2016 Get currency exchange rates in C# 12/1/2016 Get stock prices from different exchanges in C# 11/30/2016 Make mazes with topographic features in C# 11/29/2016 Make and draw a maze in C# 11/28/2016 Graph equations entered by the user in C# 11/27/2016 Graph an equation in C# 11/26/2016 Find files in the startup directory in C# 11/23/2016 Evaluate numeric expressions that are entered by the user in C# 11/23/2016 List the locations of special folders in C# 11/22/2016 List languages that you can compile at runtime in C# 11/21/2016 Run user-entered code in C# 11/18/2016 Display tooltips for ListView items in C# 11/17/2016 Sample Puzzles for Interview Puzzles Dissected 11/17/2016 Convert doc files into docx files in C# 11/16/2016 Override WndProc to see when the user clicks any control on a form in C# 11/16/2016 Save and restore line drawings in C# 11/15/2016 Center the cursor over a particular control in C# 11/14/2016 Take actions depending on the day of the week in C# 11/12/2016 Find the Friday following a given date in C# 11/11/2016 Create directories and intermediate directories in C# 11/11/2016 Book Overview Page: Interview Puzzles Dissected 11/11/2016 Table of Contents: Interview Puzzles Dissected 11/11/2016 Questions and Discussion: Interview Puzzles Dissected 11/11/2016 Book Errata Page: Interview Puzzles Dissected 11/10/2016 New Book:Interview Puzzles Dissected, Solving and Understanding Interview Puzzles 11/10/2016 Generate self-avoiding walks one at a time in C# 11/9/2016 Generate random self-avoiding walks in C# 11/8/2016 Find corner-to-corner self-avoiding walks in C# 11/7/2016 Find self-avoiding walks in C# 11/6/2016 Find the word under the mouse in a RichTextBox control in C# 11/4/2016 Enable commands in Visual Studio Express Edition 11/3/2016 Circumscribe three tangent circles in C# 11/2/2016 Overlay images in C# 11/1/2016 Draw numbered buttons and save them into files in C# 10/31/2016 Draw numbered circles and save them into files in C# 10/29/2016 Animate images in C# 10/28/2016 Draw gears in C# 10/24/2016 Simulate mouse movement and clicks in C# 10/23/2016 Let a thread call a form's methods in C# 10/21/2016 Run threads with different priorities in C# 10/20/2016 Sort words by letter count in C# 10/19/2016 Count pixels of different colors in C# 10/18/2016 Define and use bit masks in C# 10/18/2016 Understand bit masks in C# 10/17/2016 Use bit operations in C# 10/16/2016 Solve the equilateral triangles puzzle in C# 10/14/2016 Set font size to fit a wrapped label in C# 10/14/2016 Set font size to fit a label in C# 10/10/2016 Randomize two-dimensional arrays in C# 10/9/2016 Get variable values by name in C# 10/6/2016 Puzzle: Find the equilateral triangles in C# 10/4/2016 Randomly color an Apollonian gasket in C# 9/30/2016 Draw an Apollonian gasket in C# 9/28/2016 Clone lists and arrays of objects in C# 9/26/2016 Clone serializable objects in C# 9/21/2016 Find the shortest distance between a point and a line segment in C# 9/20/2016 Use MemberwiseClone the ICloneable interface in C# 9/19/2016 Clone objects in C# 9/17/2016 Convert latitudes and longitudes into distances on the globe in C# 9/16/2016 Find circles that are tangent to three given circles (Apollonius' Problem) in C# 9/16/2016 Draw three circles and find their tangent circles in C# 9/15/2016 Use steganography to hide one large picture inside another in C# 9/15/2016 Use steganography to hide one picture inside another in C# 9/14/2016 Draw a circle through three points in C# 9/13/2016 Remove the Close button from a form's system menu in C# 9/11/2016 Add delegates in C# 9/10/2016 Convert a metafile into a PNG file in C# 9/9/2016 Make a metafile in C# 9/6/2016 Display a Windows metafile (wmf) in C# 9/4/2016 Display battery status using a notify icon in C# 9/2/2016 Make a Region from non-transparent pixels in C# 8/29/2016 Scale images and save them in C# 8/27/2016 Make shaped PictureBoxes in C# 8/24/2016 Use XML comments in C# 8/22/2016 Draw trees vertically or horizontally in C# 8/20/2016 Use DrawImage to warp images in C# 8/19/2016 Warp images arbitrarily in C#, Part 2 8/18/2016 Warp images arbitrarily in C#, Part 1 8/17/2016 Compare fuel efficiency in different units in C# 8/17/2016 Compare car costs including long term mileage in C# 8/16/2016 Draw an analog clock in C# 8/15/2016 Use fuzzy lines to draw shadows in C# 8/13/2016 Play an audio resource in C# 8/13/2016 Play WAV files in C# 8/12/2016 Handle NumericUpDown value change events in C# 8/12/2016 Make a NumericUpDown use decimal values in C# 8/11/2016 Use scrollbars to select RGB and HLS colors in C# 8/11/2016 Convert between RGB and HLS color models in C# 8/10/2016 Test investment strategies with Dow Jones data in C# 8/9/2016 Graph historical Dow Jones Industrial Average values in C# 8/8/2016 Compress JPG files in a directory in C# 8/5/2016 Quickly pick JPG compression level in C# 8/5/2016 Compress JPG files to a certain size in C# 8/5/2016 Generate words of a given length in C# 8/5/2016 Generate three-letter words in C# 8/4/2016 Close Mozilla Firefox popups in C# 8/3/2016 List desktop windows in C# 8/3/2016 Load a CSV file in Excel in C# 8/2/2016 Calculate interest for a loan in C# 8/1/2016 Make an OwnerDraw ListView in C# 7/29/2016 Drag a map to scroll in C# 7/27/2016 Define map hotspots in C# 7/26/2016 Display a scalable map with hotspots in C# 7/25/2016 Display text on a ProgressBar in C# 7/23/2016 Draw justified text in C# 7/22/2016 Display map distance with limited significant digits in C# 7/21/2016 Display significant digits in C# 7/20/2016 Measure distance on a map with a scale in C# 7/16/2016 Align numeric values in ComboBox and ListBox controls in C# 7/15/2016 Sort partly numeric items in a ComboBox or ListBox in C# 7/14/2016 Link ComboBox and ListBox data sources in C# 7/14/2016 Warholize an image in C# 7/13/2016 Animate a piston driving a wheel in C# 7/12/2016 List an image's EXIF properties in C# 7/10/2016 Make an enumeration of EXIF property IDs in C# 7/7/2016 Use EXIF information to orient an image in C# 7/6/2016 Animate two rods connected to a wheel in C# 7/5/2016 Read an image file's EXIF orientation data in C# 7/4/2016 Compare speeds of arithmetic operations in C# 7/2/2016 Make two forms open each other in C# 7/1/2016 Make a robot arm track the mouse in C# 7/1/2016 Draw a robot arm with a hand that points downward in C# 6/31/2016 Draw a simple robot arm with a hand in C# 6/29/2016 Draw a simple robot arm in C# 6/28/2016 Fill a shape with random lines in C# 6/27/2016 Fill an ellipse with random lines in C# 6/24/2016 Use WPF code to display subscripts and superscripts in C# 6/24/2016 Display subscripts and superscripts in a WPF TextBlock in C# 6/23/2016 Easily display subscripts and superscripts in a RichTextBox in C# 6/22/2016 Display subscripts and superscripts in a RichTextBox in C# 6/21/2016 Calculate credit payments in C# 6/20/2016 Make a stacked graph showing compound interest in C# 6/19/2016 Show compound interest graphically in C# 6/17/2016 Calculate the value of a monthly investment in C# 6/16/2016 Split image files in C# 6/15/2016 Use a string collection setting in C# 6/6/2016 Select and print multiple files in C# 6/6/2016 Display the number of checked items in a CheckedListBox in C# 6/6/2016 Set a print job name in C# 6/6/2016 Determine the default printer in C# 6/6/2016 See how much text fits in a rectangle in C# 6/6/2016 Print a text file in C# 6/4/2016 Make a console application in C# 6/3/2016 Use the Obsolete attribute in C# 5/27/2016 Find a matrix inverse in C# 5/26/2016 Use the Conditional attribute to make a method non-callable in C# 5/25/2016 Draw smoother cones using WPF and C# 5/24/2016 Draw smooth cones using WPF and C# 5/20/2016 Draw cones using WPF and C# 5/18/2016 Make a temperature forecast in C# 5/16/2016 Get weather forecast data in C# 5/14/2016 Graph historical stock prices in C# 5/13/2016 Give an application beautiful icons in C# 5/12/2016 Provide multiple inheritance in C# 5/11/2016 Define and implement an interface in C# 5/10/2016 Display Google Maps for the computer's location in C# 5/10/2016 Use the Location API to find the computer's latitude and longitude in C# 5/9/2016 Display Google Maps for an address inside a form in C# 5/9/2016 Display Google Maps for an address in C# 5/6/2016 List birthdays in C# 5/6/2016 Use file dialog filters in C# 5/3/2016 Override a parent class method in C# 5/3/2016 Make an initializing constructor for a child class in C# 5/3/2016 Set the MessageBox default button in C# 5/2/2016 Use a custom sort order for ListBox or ComboBox items in C# 4/29/2016 Make extension methods that convert to and from Roman numerals in C# 4/29/2016 Convert to and from Roman numerals in C# 4/28/2016 Sort ListBox or ComboBox items in numeric order in C# 4/26/2016 Easily reset file access and write times in C# 4/26/2016 Make a slider with a value bar in C# 4/25/2016 Resize an image to view its pixels in C# 4/22/2016 Make a slider with a needle in C# 4/21/2016 Enumerate metafile records in C# 4/20/2016 Read and draw a metafile in C# 4/19/2016 Make and use a metafile in C# 4/15/2016 Find an image URI in a WPF program in C# 4/14/2016 Remove tabs from a WPF TabControl at runtime in C# 4/13/2016 Add tabs to a WPF TabControl at runtime in C# 4/8/2016 Use the is operator in C# 4/7/2016 Compare a list priority queue to a heap priority queue in C# 4/6/2016 Make an efficient priority queue class in C#, Part 2 4/5/2016 Make an efficient priority queue class in C#, Part 1 4/4/2016 Map between nodes and node numbers in a binary tree in C# 4/1/2016 Make animated labels in C# 4/1/2016 Draw animated text in C# 3/31/2016 Copy and paste scribble data in C# 3/31/2016 Use XOR to swap two numbers in C# 3/30/2016 Make a ComboBox display images with text in C# 3/29/2016 Make a ComboBox display colors or images in C# 3/28/2016 See if the mouse is over a curve in C# 3/27/2016 Add useful extensions to the BitArray class in C# 3/27/2016 Use the BitArray class in C# 3/26/2016 Refine the complex number class in C# 3/25/2016 Make a complex number class that works with real numbers in C# 3/24/2016 Make a complex number class with equality in C# 3/22/2016 Make a complex number class with overloaded operators in C# 3/18/2016 Compare loop performance in C# 3/18/2016 Draw 3-dimensional pie slices in C# 3/17/2016 Draw an annotated pie chart in C# 3/16/2016 Draw a labeled pie chart in C# 3/16/2016 Draw a pie chart in C# 3/16/2016 Fill and draw pie slices in C# 3/16/2016 Use yield to generate prime numbers in C# 3/14/2016 Load a WPF TreeView control from an XML file in C# 3/14/2016 Check text data type in C# 3/10/2016 Make a generic TreeNode class with link weights in C# 3/9/2016 Make a list without duplicates in C# 3/7/2016 Reset an Access autonumber field in C# 3/7/2016 Get an autonumber value that was just inserted in C# 3/5/2016 Perform multiple default actions in C# 3/5/2016 Perform a default action without an accept button in C# 3/2/2016 Interactively rotate images in C# 3/2/2016 Rotate images in C# 3/1/2016 Use SQL queries to display master-detail data in C# 2/28/2016 Generate random data in an Access database in C# 2/26/2016 Display master-detail data in a DataGrid in C# 2/25/2016 Draw a recursive overlapping snowflake fractal in C# 2/25/2016 Draw a recursive von Koch snowflake fractal in C# 2/25/2016 Draw a recursive snowflake fractal in C# 2/24/2016 Make an Excel chart in C# 2/24/2016 Graph mosquito populations in C# 2/24/2016 Simulate mosquito populations in C# 2/22/2016 Calculate a row of Pascal's triangle in C# 2/22/2016 Print a Celsius to Fahrenheit conversion chart in C# 2/20/2016 Draw a curly tree fractal using less memory in C# 2/19/2016 Draw a curly tree fractal in C# 2/18/2016 Use a scrollbar to select non-integer values in C# 2/16/2016 Display a perspective image in C# 2/16/2016 Hide the taskbar and start button in C# 2/16/2016 Make a form cover the taskbar and start button in C# 2/15/2016 Draw a colored Pickover popcorn fractal in C# 2/15/2016 Draw a Pickover popcorn fractal in C# 2/13/2016 Download images from a web page in C# 2/12/2016 Draw a 3D heart using WPF and C# 2/11/2016 Draw a parametric heart-shaped curve in C# 2/11/2016 Map drawing coordinates without distortion in C# 2/9/2016 Draw a curve with more sharply delineated colors in C# 2/9/2016 Draw a curve with sharply delineated colors in C# 2/9/2016 Draw a curve with multiple colors in C# 2/8/2016 Easily map drawing coordinates in C# 2/5/2016 Let the user select a folder in C# 2/4/2016 Convert XPS files into PNG files in C# 2/3/2016 Validate a form in C# 2/3/2016 Use the Validating event in C# 2/2/2016 Use tooltips in C# 2/1/2016 Graph the values of a savings account, 401(k), and Roth IRA in C# 2/1/2016 Compare a savings account to a 401(k) in C# 2/1/2016 Reparent a control in C# 1/29/2016 Draw four interlocking Heighway dragon fractals in C# 1/29/2016 Center a Heighway dragon fractal in C# 1/29/2016 Draw a Heighway dragon fractal in C# 1/29/2016 Control serialization and deserialization in C# 1/29/2016 Serialize and deserialize objects in C# 1/28/2016 Find a polygon union in C# 1/27/2016 Solve the skyline problem in C# 1/27/2016 Draw text on a curve in C# 1/26/2016 Draw text on a line segment in C# 1/26/2016 Position a form in the screen's lower right corner in C# 1/26/2016 Display battery status in a friendly way in C# 1/25/2016 Draw rounded rectangles in C# 1/25/2016 Get the screen's working area in C# 1/23/2016 Clip a line segment to a polygon in C# 1/22/2016 Display battery status in C# 1/16/2016 Enlarge a polygon in C# 1/14/2016 Print a calendar in C# 1/12/2016 Get the name of the first day of the week in C# 1/11/2016 Restart the print spooler in C# 1/9/2016 Display the local time and GMT in C# 1/8/2016 Get date format information for the computer's locale in C# 1/6/2016 Sort and search arrays in C# 1/5/2016 Make a rotating brush in C# 1/4/2016 Make truncated dodecahedrons in WPF and C# 1/3/2016 Make truncated tetrahedrons, octahedrons, and icosahedrons in WPF and C# 12/31/2015 Make a truncated cube in WPF and C# 12/30/2015 Initialize a Dictionary in C# 12/29/2015 Draw round circles in scaled coordinate systems in C# 12/29/2015 Initialize an array of arrays in C# 12/29/2015 Perform binary contrast enhancement interactively in C# 12/28/2015 Perform binary contrast enhancement on an image in C# 12/26/2015 Initialize two-dimensional arrays in C# 12/22/2015 Draw text with a moving brush in C# 12/21/2015 Make a moving background in C# 12/19/2015 Calculate standard deviation in C# 12/17/2015 Make a simple histogram in C# 12/16/2015 Easily draw platonic solids in WPF and C# 12/10/2015 Study WPF 3D performance in C# 12/8/2015 Make a stellate geodesic sphere with WPF and C# 12/7/2015 Build a geodesic sphere with WPF and C# 12/4/2015 Rotate a picture in C# 12/3/2015 Platonic Solids Part 8: Icosahedron and dodecahedron 12/2/2015 Platonic Solids Part 7: The dodecahedron 12/1/2015 Platonic Solids Part 6: The icosahedron 11/30/2015 Platonic Solids Part 5: Cube and octahedron 11/30/2015 Platonic Solids Part 4: The octahedron 11/29/2015 Platonic Solids Part 3: The cube 11/28/2015 Platonic Solids Part 2: The tetrahedron 11/28/2015 Platonic Solids Part 1: What are the Platonic solids? 11/24/2015 Add and remove pictures in an Excel worksheet 11/24/2015 Number files in a directory in C# 11/23/2015 Convert a directory's files to grayscale in C# 11/22/2015 Perform line clipping in C# 11/19/2015 Perform line trimming in C# 11/19/2015 Open a PDF file in C# 11/19/2015 Get the program's memory usage in C# 11/19/2015 Copy files into the executable directory in C# 11/13/2015 Save a color palette in a program's settings in C# 11/12/2015 Make a persistent color palette in C# 11/12/2015 Make a standard color palette in C# 11/12/2015 Print images in C# 11/3/2015 Make a form fade out until it disappears in C#, Part 2 11/3/2015 Make a form fade out until it disappears in C# 11/3/2015 Draw a watermark in C# 11/2/2015 Move items between two ListBoxes in C# 11/2/2015 Display font samples for all installed fonts in WPF and C# 10/30/2015 List colors in WPF and C# 10/30/2015 Bind arrays and lists in C# 10/29/2015 Set video position with a scroll bar with WPF in C# 10/28/2015 Make a XAML button library in C# 10/27/2015 Make a WPF button template in C# 10/26/2015 Control a video with the WPF MediaElement in C# 10/23/2015 Make video control buttons in WPF and C# 10/22/2015 Save WPF control images in C# 10/20/2015 Print at full scale in C# 10/20/2015 Allow limited CheckBox selection in C# 10/19/2015 Use a tristate CheckBox to show partial selections in C# 10/19/2015 Use a tristate CheckBox in C# 10/16/2015 Draw a hexagonal grid in C# 10/15/2015 Draw a triangular grid in C# 10/14/2015 Display sample formats for different locales in C# 10/14/2015 Determine which pie slice is under the mouse in C# 10/13/2015 List Dropbox directories and files in C# 10/13/2015 Select printer resolution in C# 10/10/2015 Let the user select a printer and then send a printout directly to it in C# 10/10/2015 Send a printout directly to a specific printer in C# 10/9/2015 Display Pascal's triangle in C# 10/9/2015 Change print orientation and margins in C# 10/8/2015 Make a montage editor in C#, Part 2 10/7/2015 Make a montage editor in C#, Part 1 10/6/2015 Make a Windows Phone app display icons at appropriate sizes in C# 10/5/2015 Make a Windows Store app display icons at appropriate sizes in C# 10/3/2015 Make a Windows Forms application display icons at appropriate sizes in C# 10/1/2015 Extract comments from a C# file in C# 9/29/2015 Use steganography to hide Unicode message bytes in an image in C# 9/28/2015 Use steganography to hide Unicode messages in an image in C# 9/25/2015 Draw rainbow compound lines in WPF and C# 9/24/2015 Make compound lines in WPF and C# 9/23/2015 Draw an outlined path in WPF and C# 9/22/2015 Survey: What should be in my upcoming graphics book? 9/22/2015 Draw symmetric compound lines in WPF and C# 9/21/2015 Make string extensions to URL encode and decode strings in C# 9/20/2015 Draw a histogram with tooltips in C# 9/20/2015 Draw a simple histogram in C# 9/18/2015 Use a ColorMatrix to add a watermark to an image in C# 9/18/2015 Add a watermark to an image in C# 9/17/2015 Use command bindings globally in WPF and C# 9/17/2015 Use custom command bindings in WPF and C# 9/16/2015 Use pre-defined command bindings in WPF and C# 9/16/2015 Make a selection dialog that uses a color wheel in C# 9/15/2015 Draw a color wheel with alpha and saturation values in C# 9/14/2015 Draw a colorful color wheel in C# 9/14/2015 Draw a color wheel in C# 9/14/2015 Use a notify icon to capture a screen image in C# 9/14/2015 Read and write text in text files in C# 9/11/2015 Display the predefined system icons in C# 9/10/2015 Add a UAC shield to controls in C# 9/9/2015 Plot data with standard deviation ranges in C# 9/8/2015 Draw a scaled normal distribution in C# 9/4/2015 Draw a normal distribution curve in C# 9/3/2015 Convert enum values to and from strings in C# 8/29/2015 List characters that are invalid in file and path names in C# 8/27/2015 Let the user pick database search criteria in C# 8/26/2015 Flush click events in C# 8/25/2015 Animate the Tower of Hanoi problem in C# 8/24/2015 Recursively solve the Tower of Hanoi problem in C# 8/21/2015 Animate gears with unequal sizes in C# 8/20/2015 Animate gears in C# 8/14/2015 Draw an animated atom in C# 8/13/2015 Perform Windows Forms property animation in C# 8/12/2015 Compare the performance of if-else and switch statements in C# 8/12/2015 Compare the speeds of the conditional operator (ternary operator ?:) and the if-else statement in C# 8/12/2015 Use the conditional operator (ternary operator ?:) in C# 8/10/2015 Declare and initialize empty arrays in C# 8/7/2015 Make a bobblehead in C# 8/6/2015 Draw a big-headed politician in C# 8/5/2015 Use a queue to draw a breadth-first colored binary tree in C# 8/5/2015 Draw a breadth-first colored binary tree in C# 8/4/2015 Draw a colored binary tree in C# 8/4/2015 Recursively draw a binary tree in C# 8/3/2015 Save images in an Access database in WPF and C# 7/31/2015 Display images in an Access database in WPF and C# 7/30/2015 Load an image at runtime in WPF and C# 7/29/2015 Add ComboBox choices at runtime in C# 7/28/2015 Continuously graph stock prices in C# 7/28/2015 Move a form without a title bar in C# 7/27/2015 Use image subtraction to compare images in C# 7/24/2015 Compare images to find subtle differences in C# 7/23/2015 Compare images to find differences in C# 7/23/2015 Use a loop to load pictures in C# 7/22/2015 Make a kaleidoscope program in C# 7/21/2015 Pixellate parts of an image in C# 7/20/2015 Make a closeup map in C# 7/10/2015 Set the pixels in a WPF bitmap in C# 7/10/2015 Recursively perform red eye reduction on a picture in C# 7/10/2015 Perform red eye reduction on a picture in C# 7/10/2015 Manage the recycle bin (wastebasket) in C# 7/9/2015 Use WMI to get operating system information in C# 7/9/2015 Zoom and scroll a picture drawn in C# 7/9/2015 Format DataGridView columns in C# 6/29/2015 Change audio gain in C# 6/26/2015 Plot functions in C#, Part 3 6/25/2015 Plot functions in C# 6/23/2015 Make an HTML table of thumbnail images in C# 6/22/2015 Make thumbnails and a web page to display the images in a directory in C# 6/21/2015 Find files that match multiple patterns in C# 6/19/2015 Add tabs to a TabControl at runtime in C# 6/18/2015 Notes about Windows Phone development 6/17/2015 Graph the sine, cosine, and tangent functions in C# 6/17/2015 Make an improved owner-drawn TabControl in C# 6/16/2015 Find Egyptian fractions in C# 6/15/2015 Make a Fraction class in C# 6/12/2015 Find shortest paths in a network C# 6/11/2015 Use a control array in C# 6/10/2015 Prevent Visual Studio from running programs with syntax errors 6/9/2015 Zoom and crop a picture in C# 6/8/2015 Use PixelOffsetMode in C# 6/6/2015 Crop a picture in C# 6/5/2015 Get and set file times in C# 6/4/2015 Create a Visual Studio toolbar button 6/3/2015 Create a Visual Studio tool 6/1/2015 Display line numbers in the Visual Studio code editor 5/31/2015 List the unique words in a Microsoft Word file in C# 5/29/2015 Rotate around a point other than the origin in C# 5/28/2015 Make an infinite series of menus in C# 5/27/2015 Make generic Min and Max methods in C# 5/25/2015 Create menu items at run time with images, shortcut keys, and event handlers in C# 5/23/2015 Let the user draw rubber band ellipses (or other shapes) in C# 5/20/2015 Make Windows shutdown, reboot, log off, lock, hibernate, and sleep in C# 5/18/2015 Initialize arrays with ranges or repeated values in C# 5/16/2015 Print a grid of values with alternating row colors in C# 5/15/2015 Make a countdown timer in C# 5/14/2015 Set RichTextBox tab stops in C# 5/14/2015 Format text in a RichTextBox in C# 5/13/2015 Make a class that wraps arrays with non-zero lower bounds in C# 5/12/2015 Make a default indexer property for a class in C# 5/11/2015 Make arrays with non-zero lower bounds in C# 5/10/2015 Copy arrays quickly in C# 5/8/2015 Draw a variety of fractal strange attractors in C# 5/8/2015 Draw stars inside polygons in C# 5/8/2015 Render text onto a RenderTargetBitmap with WPF and C# 5/8/2015 Get font metrics in a WPF program using C# 5/4/2015 Easily render rotated text in a WPF program using C# 5/1/2015 Render text filled with an image in a WPF program using C# 4/30/2015 Render outlined text in a WPF program using C# 4/29/2015 Render text easily in a WPF program using C# 4/29/2015 Render text in a WPF program using C# 4/28/2015 Render polygons and polylines in a WPF program using C# 4/27/2015 Render dashed lines in a WPF program using C# 4/26/2015 Render an ellipse in a WPF program using C# 4/25/2015 Remove part of an image in C# 4/24/2015 Size a font to fit a Label in C# 4/23/2015 FREE Book Drawing: Beginning Software Engineering 4/20/2015 Display an end user license agreement (EULA) in C# 4/19/2015 Generate a schedule for a round robin tournament in C# 4/17/2015 Animate a rectangle moving along a path in WPF and C# 4/16/2015 Draw smooth spheres using WPF and C# 4/15/2015 Draw spheres using WPF and C# 4/14/2015 Draw smooth cylinders using WPF and C# 4/13/2015 Draw cylinders using WPF and C# 4/11/2015 Remove non-digits or non-letters from a string in C# 4/10/2015 Draw a 3D surface from a set of data points with an altitude map using WPF and C# 4/9/2015 Merge splash screens and videos in a directory in C# 4/8/2015 Merge videos in C# 4/7/2015 Change video quality in C# 4/6/2015 Draw a curve with negative tension in C# 4/3/2015 Draw a curve with varying tensions in C# 4/2/2015 Change tension for a smooth curve in C# 4/1/2015 New Book: Beginning Software Engineering 4/1/2015 Draw a smooth curve connecting points in C# 3/31/2015 Let the user zoom on a picture in C# 3/30/2015 Provide autosave in C# 3/27/2015 Provide undo and redo in C# 3/26/2015 Save and restore pictures drawn by the user in C# 3/25/2015 Let the user scribble with different line styles in C# 3/24/2015 Let the user scribble on a PictureBox in C# 3/20/2015 Use steganography to hide one large picture inside another in C# 3/19/2015 Use steganography to hide one picture inside another in C# 3/18/2015 Use steganography to hide messages in an image in C# 3/17/2015 Graph several pi approximations in C# 3/16/2015 Approximate pi using several different methods in C# 3/15/2015 Graph pi approximations in C# 3/14/2015 In honor of Pi Day (3.14), approximate pi in C# 3/12/2015 Use set operators in C# 3/10/2015 Perform set operations in C# 3/9/2015 (Book review) Essential Algorithms: A Practical Approach to Computer Algorithms 3/9/2015 Obscure parts of a picture for privacy in C# 3/6/2015 Understand event bubbling and tunneling in WPF and C# 3/5/2015 Get the executing method name in C# 3/4/2015 Enumerate pairs of objects in arrays or IEnumerables in C# 3/3/2015 Use vectors to manage bouncing balls in C# 3/2/2015 Use sprites to animate several bouncing balls in C# 3/1/2015 Animate several bouncing balls in C# 2/28/2015 Make a bouncing ball animation in C# 2/27/2015 Make a WPF line editor C# 2/25/2015 Measure character positions when drawing long strings in C# 2/24/2015 Play tones with specific frequencies in C# 2/23/2015 Play a WAV file in C# 2/20/2015 Play an audio resource in C# 2/18/2015 Drag and drop images while displaying a preview in C# 2/18/2015 Drag and drop text with feedback in C# 2/18/2015 Drag and drop images in C# 2/18/2015 Drag and drop text in C# 2/17/2015 Add a ToString extension method to the TimeSpan structure in C# 2/16/2015 Find elapsed time in years, months, days, hours, minutes, and seconds in C# 2/15/2015 Find the days, hours, minutes, or seconds between two dates in C# 2/13/2015 Draw a family tree in C# 2/12/2015 Draw a tree with nodes containing pictures in C# 2/11/2015 Handle generic TreeNode mouse events in C# 2/10/2015 Make a generic TreeNode class in C#, Part 2 2/9/2015 Make a generic TreeNode class in C#, Part 1 2/6/2015 Make a generic priority queue class in C# 2/4/2015 Draw lines with custom end caps in C# 2/4/2015 Draw lines with end caps in C# 2/4/2015 Draw lines with custom dash patterns in C# 2/3/2015 Draw dashed lines with different dash cap styles in C# 2/3/2015 Draw dashed lines with different styles in C# 2/2/2015 Use WMI to get the number of physical and logical processors in C# 2/1/2015 Use branch and bound with an initial heuristic to solve the partition problem in C# 1/31/2015 Use branch and bound to solve the partition problem in C# 1/30/2015 Use exhaustive search to solve the partition problem in C# 1/29/2015 Run a DOS application and capture its output in C# 1/28/2015 Make CAPTCHA images with overlapping characters in C# 1/28/2015 Make CAPTCHA images in C# 1/26/2015 Draw a Sierpinski carpet in C# 1/26/2015 Draw a Sierpinski triangle in C# 1/26/2015 Make menus at run time for a WPF application in C# 1/22/2015 Print stars in C# 1/21/2015 Get file size and last modification time on an FTP server in C# 1/20/2015 Upload files to an FTP server in C# 1/20/2015 Upload text into a file on an FTP server in C# 1/19/2015 Graph stock prices downloaded from the internet in C# 1/17/2015 Convert between long and short file names in C# 1/16/2015 Get stock prices from the internet in C# 1/16/2015 Change program locale at runtime in C# 1/16/2015 Test localized programs in C# 1/13/2015 Localize a program in C# 1/12/2015 Select N random items from an array in C# 1/12/2015 Select random objects from an array in C# 1/11/2015 Draw, move, and delete line segments in C# 1/7/2015 Understand taxicab numbers in C# 1/6/2015 Make owner drawn tooltips with pictures in C# 1/6/2015 Make owner drawn menus in C# 1/6/2015 Calculate Nth roots in C# 1/5/2015 List unique words in a text file in C# 1/5/2015 Access firewall information and check firewall status using the dynamic keyword in C# 1/5/2015 Display Unicode symbols in C# 1/4/2015 Draw a Phoenix set fractal in C# 1/4/2015 Draw smooth graphics in C# 12/31/2014 Draw on a bitmap in C# 12/30/2014 Draw in a Paint event handler in C# 12/29/2014 Let controls share event handlers in C# 12/28/2014 Use the params keyword in C# 12/27/2014 Split and join strings in C# 12/26/2014 Get the system's board serial numbers and CPU IDs in C# 12/24/2014 Make a blinking label in WPF and C# 12/22/2014 Let the user move and resize a rectangle in WPF and C# 12/20/2014 Register a program for a particular system in C# 12/20/2014 Set form client size in C# 12/20/2014 Size forms to fit their contents in C# 12/19/2014 Draw a Bezier curve by hand in C# 12/19/2014 Draw a Bezier curve in C# 12/19/2014 Find, open, and replace text in files in C# 12/18/2014 Find files and replace text in them in C# 12/16/2014 Improve the jigsaw puzzle program in C# 12/15/2014 Make a jigsaw puzzle in C# 12/11/2014 Send secret Santa emails in C# 12/9/2014 Calculate the number of secret Santa permutations in C# 12/8/2014 Pick a secret Santa assignment in C# 12/6/2014 Send email in C# 12/5/2014 Make extension methods that randomize arrays and lists in C# 12/5/2014 Draw lines with arrowheads in C# 12/5/2014 Display unique progress bars in C# 12/4/2014 Review of my book C# 5.0 Programmer's Reference 12/4/2014 Partition an area with circles and draw each region's count in C# 12/2/2014 Display a simple password dialog before a program starts in C# 12/1/2014 Find a Region centroid in C# 12/1/2014 Find the area where circles overlap in C# 12/1/2014 Find the tangent lines between two circles in C# 11/30/2014 Remove the hyperlinks from a Word document in C# 11/30/2014 Find the tangent lines between a point and a circle in C# 11/29/2014 Print a form or control in C# 11/29/2014 Force garbage collection in C# 11/28/2014 Handle DataGridView errors in C# 11/28/2014 Build a DataTable and bind it to a DataGridView in C# 11/28/2014 Bind a DataGrid to a DataSet holding multiple tables at runtime in C# 11/27/2014 List OLE DB providers installed on the system in C# 11/27/2014 Draw a labeled line graph that displays value tooltips in C# 11/27/2014 Map points between coordinate systems in C# 11/27/2014 Execute ad hoc SQL commands in C# 11/26/2014 Execute ad hoc SQL queries in C# 11/26/2014 Compare LINQ speeds for different approaches in C# 11/26/2014 Use LINQ to find a bounding box for a list of PointF in C# 11/26/2014 Use LINQ Min, Max, and Average extension methods in C# 11/25/2014 Read a CSV file into an array in C# 11/25/2014 Use Newton's method to draw fractals for polynomial equations in C# 11/25/2014 Use Newton's method to draw fractals for equations of the form F(z) = z^C - C^z in C# 11/25/2014 Use Newton's method to draw a fractal in C# 11/23/2014 Make a modal context menu in C# 11/22/2014 How to become an expert programmer 11/18/2014 Make an owner-drawn ListBox with pictures in C# 11/17/2014 Make an owner-drawn ListBox in C# 11/15/2014 Get the current time from the NIST server in C# 11/15/2014 Convert dates into an ordinal format (as in August 20th, 2020) in C# 11/15/2014 Convert an integer into an ordinal (1st, 2nd, 3rd) in C# 11/15/2014 Add a picture to a Word document in C# 11/15/2014 Create a Word document in C# 11/15/2014 Draw a filled chrysanthemum curve in C# 11/15/2014 Draw a chrysanthemum curve in C# 11/11/2014 See where a line intersects a conic section in C# 11/10/2014 See where two conic sections intersect in C# 11/10/2014 Select a conic section in C# 11/10/2014 See where a parabola and hyperbola intersect in C# 11/9/2014 Read Excel data in C# 11/9/2014 Write Excel data in C# 11/8/2014 Control the print preview dialog in C# 11/7/2014 Scale a drawing to fit a target area in C# 11/7/2014 Use double buffering to prevent flicker in a PictureBox in C# 11/7/2014 Use double buffering to prevent flicker when drawing in C# 11/7/2014 Draw a colored butterfly curve in C# 11/7/2014 Draw an animated epitrochoid in C# 11/7/2014 Draw an epitrochoid in C# 11/7/2014 Use TabControl accelerators in C# 11/6/2014 Make an owner-drawn TabControl in C# 11/6/2014 Generate and display HTML in C# 11/5/2014 Understand C# regular expression symbols 11/5/2014 Replace text in the lines of a string in C# 11/5/2014 Replace text matching a pattern in C# 11/5/2014 Show regular expression matches in C# 11/4/2014 Use a BackgroundWorker in C# 11/3/2014 Use multiple threads to draw a graph in C# 11/2/2014 Draw a conic section from its polynomial equation in C# 11/2/2014 See where two ellipses intersect in C#, Part 4 11/2/2014 See where two ellipses intersect in C#, Part 3 11/2/2014 See where two ellipses intersect in C#, Part 2 11/2/2014 See where two ellipses intersect in C#, Part 1 11/1/2014 Use Newton's method to find the roots of equations in C# 11/1/2014 Calculate the formula for an ellipse selected by the user in C# 11/1/2014 Calculate the formula for a circle selected by the user in C# 10/31/2014 Select parts of a scaled image in a PictureBox with different SizeMode values in C# 10/30/2014 Find a least squares Weibull curve fit for a set of points in C# 10/30/2014 Find an exponential least squares fit for a set of points in C# 10/30/2014 Find a polynomial least squares fit for a set of points in C# 10/30/2014 Find a linear least squares fit for a set of points in C# 10/30/2014 Solve a system of equations with Gaussian elimination in C# 10/29/2014 Display custom colors in the color selection dialog in C# 10/29/2014 Clean a WordPress database in C# 10/28/2014 Rainbowize an image in C# 10/28/2014 Use an ImageAttributes object to apply general color tones to an image in C# 10/28/2014 Use an ImageAttributes object to convert an image to shades of red, green, or blue in C# 10/28/2014 Use an ImageAttributes object to convert an image to sepia tone in C# 10/28/2014 Use an ImageAttributes object to convert an image to monochrome in C# 10/28/2014 Use an ImageAttributes object to adjust an image's brightness in C# 10/27/2014 Quickly convert an image to grayscale in C# 10/24/2014 Validate a switch statement that uses values from an enumerated type in C# 10/24/2014 Let the user select and deselect 3D objects using WPF and C# 10/23/2014 Perform hit testing in a 3D program that uses WPF, XAML, and C# 10/22/2014 Use segments to draw 3D axes with tic marks using WPF and C# 10/22/2014 Use segments to draw 3D arrows using WPF and C# 10/22/2014 Draw triangle vertex normals on a 3D model using WPF and C# 10/21/2014 Draw surface normals on a 3D model using WPF and XAML 10/20/2014 Draw a 3D wireframe using WPF and C# 10/18/2014 Draw improved 3D line segments using WPF and C# 10/18/2014 Draw interlocked tetrahedrons in a cage of "line segments" using WPF and C# 10/18/2014 Draw two interlocked tetrahedrons defined by a cube using WPF and C# 10/17/2014 Use a dictionary to draw a 3D Menger sponge fractal more efficiently using WPF, XAML, and C# 10/17/2014 Draw a 3D Menger sponge fractal using WPF, XAML, and C# 10/16/2014 Apply textures to triangles using WPF and C# 10/15/2014 Fully justify paragraphs of text in C# 10/15/2014 Fully justify a line of text in C# 10/14/2014 Create a 3D surface really quickly with WPF, XAML, and C# 10/14/2014 Create a 3D surface more quickly with WPF, XAML, and C# 10/14/2014 Draw a smooth 3D surface with WPF, XAML, and C# 10/13/2014 Draw a 3D surface with WPF, XAML, and C# 10/13/2014 Understand three-dimensional drawing with WPF, XAML, and C# 10/13/2014 Use static resources to customize a XAML program 10/13/2014 Use static resources to draw three interlocked boxes using XAML and C# 10/13/2014 Draw three interlocked boxes using XAML and C# 10/13/2014 Draw interlocked tetrahedrons using XAML and C# 10/13/2014 Rotate a tetrahedron with crisp edges using XAML and C# 10/13/2014 Rotate a tetrahedron using XAML and C# 10/13/2014 Make a 3D cube with pictures on its sides with XAML and C# 10/12/2014 Make a continuously spinning 3D cube with XAML and C# 10/12/2014 Rotate a 3D cube using XAML and C# 10/10/2014 Draw a 3D surface overlaid with a shaded altitude map using WPF and C# 10/10/2014 Draw a 3D surface overlaid with a grid using WPF and C# 10/10/2014 Initialize a ComboBox from an enumeration in C# 10/10/2014 Convert between Pascal case, camel case, and proper case method 2 in C# 10/10/2014 Convert between Pascal case, camel case, and proper case in C# 10/9/2014 Draw and move polygons snapping them to a grid in C# 10/8/2014 Let the user draw polygons, move them, and add points to them in C# 10/7/2014 Let the user draw and move polygons in C# 10/7/2014 Let the user draw polygons in C# 10/6/2014 Draw and move line segments snapping to a grid in C# 10/5/2014 Draw and move line segments in C# 10/4/2014 Use a GraphicsPath to determine whether a point lies inside a polygon in C# 10/4/2014 Use the File.Replace method to backup files in C# 10/4/2014 Make a log file with multiple overflow versions in C# 10/4/2014 Use the Debug class's Assert method to find bugs in C# 10/2/2014 Use a NotifyIcon in C# 10/1/2014 Make a close-up window for an image in C# 10/1/2014 Draw 2D and 3D borders in C# 9/30/2014 Use nullable parameters in C# 9/30/2014 Use null to simulate optional parameters in C# 9/30/2014 Use overloaded methods to simulate optional parameters in C# 9/30/2014 Calculate and highlight DataGridView values in C# 9/30/2014 Initialize DataGridView controls with objects in C# 9/29/2014 Draw a colored fractal curve generated by prime numbers in C# 9/29/2014 Draw a fractal curve generated by prime numbers in C# 9/29/2014 Set DataGridView column styles in C# 9/29/2014 Use the predefined system colors in C# 9/29/2014 Encrypt or decrypt files in C# 9/26/2014 Convert between byte arrays and hexadecimal strings in C# 9/26/2014 Generate random strings in C# 9/26/2014 Draw a fractal generated by prime numbers in C# 9/26/2014 Map numeric values to and from colors in a color gradient in C# 9/26/2014 Map numeric values to and from colors in a color gradient in C# 9/25/2014 Let the user drag an image with transparent pixels over a background image in C# 9/24/2014 Zoom on a graph with XAML code in C# 9/24/2014 Zoom on a graph in WPF and C# 9/24/2014 Let the user click on graph points in WPF and C# 9/23/2014 Draw a graph with rotated text in WPF and C# 9/23/2014 Draw a graph with labels in WPF and C# 9/22/2014 Draw a graph with even tic marks in WPF and C# 9/21/2014 Use transformations to draw a graph in WPF and C# 9/20/2014 Draw a graph in WPF and C# 9/19/2014 See what kinds of data are available in the clipboard and display them in C# 9/19/2014 Get the image of a control or form, or a form's client area in C# 9/19/2014 Save an image of the computer's screen in a file in C# 9/19/2014 Copy and paste data in multiple formats to the clipboard in C# 9/19/2014 Copy and paste objects to the clipboard in C# 9/19/2014 Print data in rows and columns in C# 9/18/2014 Use the DotNetZip library to compress and decompress files in C# 9/18/2014 Draw level curves for an array of z values in C# 9/17/2014 Draw level curves for functions of two variables z = F(x, y) in C# 9/17/2014 Plot a heart-shaped function in C# 9/17/2014 Use a type converter with a PropertyGrid control in C# 9/17/2014 Use PropertyGrid descriptions and categories in C# 9/17/2014 Use a PropertyGrid to let the user edit objects in C# 9/17/2014 Make a shaped form by setting its region in C# 9/16/2014 Plot a smiley face function in C# 9/16/2014 Pass a method to another method in C# 9/16/2014 Plot an equation containing two variables in C# 9/15/2014 Sort a ListView using the column you click in C# 9/14/2014 Sort a ListView control using all of its columns in C# 9/14/2014 Implement an interface in C# 9/14/2014 Draw text filled with a picture in C# 9/14/2014 Use VBA code to pick random cells from the currently selected cells in an Excel workbook 9/13/2014 What is WPF and why should you care? 9/12/2014 Use regular expressions to rename files within a date range and that match a pattern in C# 9/12/2014 Write a graphical floodfill method in C# 9/12/2014 Paste a PNG format image with a transparent background from the clipboard in C# 9/12/2014 Copy an irregular area from a picture to the clipboard in C# 9/12/2014 Copy an irregular area from one picture to another in C# 9/11/2014 Find the ListView row and column under the mouse in C# 9/11/2014 Easily add column headers and items to a ListView control in C# 9/11/2014 Use regular expressions to rename files that match a pattern in C# 9/10/2014 Format an XML file so it looks nice in C# 9/10/2014 Use objects to make an XML document in C# 9/10/2014 Build a formatted XML document in memory in C# 9/10/2014 Load a TreeView from a tab-delimited file in C# 9/10/2014 Load a TreeView control from an XML file in C# 9/10/2014 Automatically resize ListView columns to fit their data in C# 9/10/2014 Copy data in a two-dimensional array into a ListView control in C# 9/10/2014 Use the Bitmap class's RotateFlip method to easily flip and rotate an image in C# 9/9/2014 Use an event handler for multiple controls in C# 9/9/2014 Invoke public methods by using their names in C# 9/9/2014 Use DrawPolygon and DrawLines to draw shapes (and understand the different results) in C# 9/9/2014 Explore Unicode characters in C# 9/8/2014 Use preprocessor directives in C# 9/8/2014 Use mathematical and other special symbols in HTML code 9/8/2014 Display animated GIFs and change them at run time in C# 9/8/2014 Draw a skewed Sierpinski gasket with any number of corners in C# 9/6/2014 Draw a Sierpinski gasket in C# 9/6/2014 Determine where two circles intersect in C# 9/5/2014 Determine where a line intersects a circle in C# 9/5/2014 Use WPF to make a download button in C# 9/4/2014 Draw an ellipse that sort of looks like a button in C# 9/4/2014 Use the using statement to automatically call Dispose in C# 9/3/2014 Redraw a form whenever it resizes in C# 9/3/2014 Compare the speeds of different methods for string concatenation in C# 9/3/2014 Draw a Pickover strange attractor fractal in C# 9/3/2014 Make an extender provider that validates required TextBoxes in C# 9/2/2014 Learn why a form is closing in C# 9/2/2014 Apply a filter to make a color embossed image in C# 9/2/2014 Pixellate an image and create other effects in C# 9/2/2014 Use image filters to perform edge detection, smoothing, embossing, and more in C# 9/2/2014 Convert bases decimal, hexadecimal, octal, and binary in C# 9/2/2014 Understand font aliasing issues in C# 8/29/2014 Use value equality to compare font objects in C# 8/29/2014 Display a font selection dialog with an Apply button in C# 8/29/2014 Make a program display its own binary code in three ways in C# 8/27/2014 Use the Bitmap32 class to manipulate image pixels very quickly in C# 8/27/2014 Add GetPixel and SetPixel methods to the Bitmap24 class in C# 8/27/2014 Use the Bitmap24 class to manipulate image pixels very quickly in C# 8/27/2014 Let the user move the center point of elliptical gradient in C# 8/27/2014 Fill an area with an elliptical gradient in C# 8/27/2014 Fill a polygon with a PathGradientBrush in C# 8/27/2014 Use a LinearGradientBrush in C# 8/26/2014 Select full rows in a ListView and store extra information with ListView rows in C# 8/26/2014 Parse currency values in C# 8/25/2014 Draw striped lines in C# 8/25/2014 Draw a star with a given number of points in C# 8/25/2014 Draw a non-intersecting star in C# 8/25/2014 Draw a star in C# 8/23/2014 See a review of my book "C# 5.0 Programmer's Reference" at the Denver Visual Studio User Group web site 8/23/2014 See how much time a checked block takes in C# 8/23/2014 Control overflow behavior with checked and unchecked in C# 8/22/2014 Use a bitmap to visualize composite runs in C# 8/22/2014 Find runs of composite numbers (non-primes) in C# 8/21/2014 Use a bitmap to visualize odd primes in C# 8/21/2014 Use a bitmap to visualize primes in C# 8/21/2014 Use Euler's Sieve to find prime numbers in C# 8/21/2014 Use the Sieve of Eratosthenes to find prime numbers in C# 8/21/2014 Make a checked GroupBox in C# 8/21/2014 Change control stacking order in C# 8/20/2014 Make menu items behave like check boxes in C# 8/20/2014 Make toolstrip buttons act like radio buttons in C# 8/20/2014 Make menu items act like radio buttons in C# 8/19/2014 Select ComboBox or ListBox values that contains target text in C# 8/19/2014 Draw a timezone conversion chart in C# 8/19/2014 Use Microsoft Word to make a timezone conversion chart in C# 8/19/2014 List the defined locales in C# 8/19/2014 List timezones in C# 8/19/2014 Use custom numeric formats in C# 8/19/2014 Use custom date and time formats in C# 8/19/2014 Use standard numeric formats in C# 8/19/2014 Use standard date and time formats in C# 8/19/2014 Use the DateTime class's standard formatting methods in C# 8/19/2014 Use ListView data to generate HTML TABLE code in C# 8/19/2014 Use groups in a ListView control in C# 8/18/2014 Draw text filled with random colored circles in C# 8/18/2014 Draw text filled with random colored lines in C# 8/18/2014 Draw text in random colors in C# 8/18/2014 Draw text filled with random lines in C# 8/18/2014 Draw text filled with text in C# 8/18/2014 Draw hollow text in C# 8/17/2014 Use try catch blocks to protect against unexpected errors in C# 8/15/2014 Use TryParse to parse values entered by the user in C# 8/15/2014 Parse user-entered values in C# 8/15/2014 Draw a smooth vortex fractal in C# 8/15/2014 Draw a vortex fractal in C# 8/15/2014 Draw a curlicue fractal in C# 8/15/2014 Draw rainbow text in C# 8/15/2014 Get font metrics in C# 8/15/2014 Measure character positions in a drawn string in C# 8/15/2014 Use LINQ to list files and file sizes in a directory in C# 8/14/2014 Use reflection to enumerate HatchStyle values and display samples of them in C# 8/14/2014 Use reflection to easily list the values defined by an enumerated type in C# 8/14/2014 Use reflection to list the values defined by an enum in C# 8/14/2014 Display images of the cursors available in C# 8/14/2014 Copy, cut, and paste parts of an image to the clipboard in C# 8/13/2014 Use a rubber band box to let the user select an area in a picture in C# 8/13/2014 Find a minimal bounding circle of a set of points in C# 8/13/2014 Draw a circle through three points in C# 8/12/2014 Find the shortest distance between two line segments in C# 8/12/2014 Determine where two lines intersect in C# 8/12/2014 Copy and paste text to and from the clipboard C# 8/12/2014 Calculate the factorial function and use Debug.Assert in C# 8/12/2014 Give classes auto implemented properties and initializing constructors in C# 8/12/2014 Initialize arrays, lists, and class instances in C# 8/12/2014 Override a class's ToString method to allow controls such as ListBox to display objects in C# 8/12/2014 Start another program and wait until it finishes in C# 8/12/2014 Open a file with the system's default application in C# 8/12/2014 Combine and resolve relative paths in C# 8/11/2014 Draw an animated hypotrochoid (Spirograph curve) in C# 8/11/2014 Draw a hypotrochoid (Spirograph curve) in C# 8/11/2014 Calculate the GCD (greatest common divisor) and LCM (least common multiple) of two integers in C# 8/10/2014 Generate all selections of K items from a set of N items in C# 8/10/2014 Calculate the binomial coefficient "N choose K" efficiently in C# 8/10/2014 Generate all of the permutations of a set of objects in C# 8/10/2014 Make a notepad application that uses encryption in C# 8/10/2014 Make a password manager in C# 8/8/2014 Use cryptographic methods to generate random passwords in C# 8/8/2014 Use a cryptographic random number generator in C# 8/8/2014 Use the .NET cryptography library to make extension methods that encrypt and decrypt strings in C# 8/7/2014 Protect a program from SQL injection attacks in C# 8/5/2014 Use WMI to get information including the operating system's name in C# 8/5/2014 Make a web browser that only allows certain web sites in C# 8/5/2014 Provide printing and print previews with advanced features for Windows Forms applications in C# 8/4/2014 Provide print previews and printing for Windows Forms applications in C# 8/4/2014 Create controls for a tic-tac-toe application at run time in C# 8/3/2014 Make a shaped button in C# 8/1/2014 Use the TableLayoutPanel control in C# 8/1/2014 Post some book reviews! 7/31/2014 Find a number's prime factors in C# 7/30/2014 Perform geometric operations on polygons in C# 7/29/2014 Find a minimal bounding rectangle for a polygon in C# 7/29/2014 Triangulate a polygon in C# 7/29/2014 Find the centroid of a polygon in C# 7/29/2014 Reverse the orientation of a polygon in C# 7/29/2014 Determine whether a polygon is oriented clockwise or counterclockwise in C# 7/28/2014 Calculate the area of a polygon in C# 7/28/2014 Determine whether a point is inside a polygon in C# 7/28/2014 Determine whether a polygon is convex in C# 7/27/2014 Draw a Sierpinski fractal curve in C# 7/27/2014 Draw a strange attractor fractal in C# 7/27/2014 Make a dialog with standard dialog features in C# 7/25/2014 Use standard dialogs in C# 7/25/2014 Use WndProc to read Windows messages in C# 7/24/2014 Find the convex hull of a set of points in C# 7/24/2014 Align text drawn by DrawString in C# 7/23/2014 Sort objects in C# 7/23/2014 Use WMI to get detailed printer information in C# 7/23/2014 Display font samples on a computer in C# 7/22/2014 Let the user select rectangular areas in an image in C# 7/22/2014 Optimize JPEG compression level and file size in C# 7/22/2014 Format file sizes in KB, MB, GB, and so forth in C# 7/22/2014 Easily save and restore a form's settings in the Registry in C# 7/22/2014 Change image file types in a directory in C# 7/21/2014 C# Helper RSS feed 7/21/2014 Resize pictures in a directory in C# 7/21/2014 Resize images and save the results in C# 7/21/2014 Save images with an appropriate format depending on the file name's extension in C# 7/21/2014 Load images without locking their files in C# 7/20/2014 Save and restore program settings in C# 7/20/2014 Calculate logarithms in different log bases in C# 7/19/2014 Convert between Excel column numbers and names in C# 7/19/2014 Make a transparent form and let the user move it in C# 7/17/2014 Set tab positions inside a ListBox or TextBox in C# 7/17/2014 Draw a Mandelbrot set fractal with smoothly shaded colors in C# 7/17/2014 Use a Complex number class to draw a Mandelbrot set fractal easily in C# 7/17/2014 Draw a Mandelbrot set fractal in C# 7/16/2014 Programmatically adjust the splitter in a SplitContainer control in C# 7/16/2014 List installed fonts on your system in C# 7/16/2014 Get command line arguments in C# 7/16/2014 Calculate compound interest over time in C# 7/16/2014 Find controls by name in C# 7/16/2014 Make a string extension to determine whether a string matches a regular expression in C# 7/16/2014 Make random groups of people or other objects in C# 7/14/2014 Randomize arrays in C# 7/13/2014 Make an extension method to convert numbers into words (as in "one thousand eight hundred twelve") in C# 7/13/2014 Evaluate mathematical expressions with code in C# 7/13/2014 Download files from the web in C# 7/13/2014 Execute ad hoc database commands such as CREATE TABLE, INSERT INTO, DROP TABLE, and so forth in C# 7/12/2014 Measure elapsed time in C# 7/12/2014 Use resources to hold images, text, and other data, and load it at run time in C# 7/12/2014 Place a notify icon in the notification area in C# 7/12/2014 Search files in a directory hierarchy for a target string in C# 7/12/2014 Create controls at runtime and add them to a form or inside a container in C# 7/11/2014 Draw a Barnsley fern fractal in C# 7/11/2014 Override ToString to allow controls such as ListBox to display objects in C# 7/11/2014 Draw rotated text in C# 7/11/2014 Add items to the Send To menu 7/11/2014 Programmatically add new rows to an unbound DataGridView control in C# 7/11/2014 Draw a Buddhabrot fractal in C# 7/11/2014 Draw a Hilbert curve fractal in C# 7/10/2014 Test different methods that compare directories to see which files they have in common in C# 7/10/2014 Compare directories to see which files they have in common in C# 7/10/2014 Draw backwards text in C# 7/10/2014 Get information about a disk drive such as size and available space in C# 7/10/2014 Play system sounds: beep, asterisk, question, etc. in C# 7/9/2014 Problems with comments and links in older posts 7/9/2014 The older C# Helper blog posts are once again available 7/8/2014 Switching the blog to WordPress 6/26/2014 Welcome!