Category Archives: extensions

Make bitmap extension methods that resize bitmaps in C#

Posted on April 27, 2020 by RodStephens

The post Resize pictures in a directory to specific widths or heights in C# lets you resize all of the pictures in a directory. This example extracts the key method that resizes files and places it in a new Bitmap … Continue reading →

Posted in extensions, files, graphics | Tagged , , , , , , , , , , , , , , , , | 2 Comments

Make a TextBox preview extender provider in C#

Posted on August 22, 2017 by Rod Stephens

This example shows how to convert the TextBox preview techniques described in the last few posts into an extender provider. The previous examples showed the basic technique, but they were hard-wired to specific TextBox controls so they weren’t very flexible. … Continue reading →

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Use string extension methods to validate Social Security numbers in C#

Posted on June 19, 2017 by Rod Stephens

This example defines three extension methods that return true if strings contain Social Security numbers. Recall that you must add extension methods to a static class and that the methods must be static. This example begins by defining a Matches … Continue reading →

Posted in extension methods, extensions, regular expressions, strings | Tagged , , , , , , , , , | 5 Comments

Add an extension method to the Graphics class in C#

Posted on September 14, 2016 by Rod Stephens

For some strange reason, the Graphics class’s DrawRectangle method cannot take a RectangleF as a parameter. It can take a Rectangle or four float values, and the FillRectangle method can take a RectangleF as a parameter, but the DrawRectangle method … Continue reading →

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Make string extensions to URL encode and decode strings in C#

Posted on September 21, 2015 by Rod Stephens

When you URL encode a string, you convert special characters into numeric sequences thath are safe to use in a URL. When you URL decode a string, you reverse the process. The following code creates extension methods for the string … Continue reading →

Posted in extension methods, extensions, strings | Tagged , , , , , , , , , , | 1 Comment

Convert between byte arrays and hexadecimal strings in C#

Posted on September 26, 2014 by Rod Stephens

This example uses extension methods to convert between byte arrays and hexadecimal strings. It adds a ToHex extension method to the byte[] type and a ToBytes extension method to the string class. To create an extension method, create a public … Continue reading →

Posted in algorithms, cryptography, extensions, strings | Tagged , , , , , , , , , , , , , , , | 2 Comments

Use the BitConverter class to write extension methods to convert between byte arrays and strings of hexadecimal values in C#

Posted on January 11, 2014 by Rod Stephens

This is a new version of the example Write extension methods to convert between byte arrays and strings of hexadecimal values in C# that takes a slightly different approach. The following code shows the new versions of the extension methods. … Continue reading →

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