Tag Archives: strings

Efficiently see if a string is blank in C#

This example uses three strings to compare different methods for determining whether a string is blank. One of the methods, the string class’s IsNullOrWhiteSpace method, only works in .NET Framework 4.5 or later, so this example targets that version of … Continue reading

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Examine the unique words in a Microsoft Word file in C#

This example is a modification of the earlier post List the unique words in a Microsoft Word file in C#. That program reads the words in a Microsoft word file, sorts them, and then displays the unique words in a … Continue reading

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

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

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Understand the @ symbol in C#

The @ symbol can be pretty confusing for some C# developers. I’ve even known a few who have been programming for quite a while but who still have incorrect assumptions about what @ does. In your code (and only in … Continue reading

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Use digits of Pi to draw a picture in C#

The article 10 stunning images show the beauty hidden in pi shows several ways to use Pi to generate pictures. This example demonstrates one of them. The program starts drawing at the origin (0, 0). It then scans through the … Continue reading

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Look for dates in the digits of Pi in C#

The example Find patterns within pi in C# looks for patterns within the digits of Pi. You can use that example to look for dates such as 4/1. This example determines whether the first 100 thousand digits of Pi contains … Continue reading

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Find patterns within Pi in C#

March 14 is known as Pi Day because its numeric representation 3/14 includes the first three digits of Pi: 3.14. (At least in the United States. In Europe where they usually write dates month first, Pi Day is July 22 … Continue reading

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Make a case-insensitive dictionary in C#

The example Use a Dictionary to store and retrieve items in C# shows how to use a dictionary to store and retrieve values with keys. By default the Dictionary class is case-sensitive so the keys “Rod Stephens” and “rod stephens” … Continue reading

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Understand string equality testing in C#

To really understand this example, you need to know about string interning, equality testing, and operator overloading. Interning First, interning. To save space, .NET uses an intern pool to store literal strings at compile time. If the program contains a … Continue reading

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Use a Dictionary to store and retrieve items in C#

This example demonstrates a Dictionary. A Dictionary is basically a strongly typed Hashtable. A Hashtable stores key/value pairs in a way that makes looking up values extremely fast. For example, suppose you have an employee database that uses EmployeeId values … Continue reading

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