Determine whether a string contains a specific substring in C#

This post will discuss how to determine whether a string contains a specific substring in C#.

You can use the String.Contains() method, which returns a boolean value indicating whether the specified substring occurs within the string. The following example demonstrates its usage.

using System;

public class Example

{

public static void Main()

{

string str = "100$";

string sub = "$";

bool exist = str.Contains(sub);

Console.WriteLine(exist); // True

}

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The String.Contains() method performs a case-sensitive comparison. To perform the culture-insensitive comparison, you can directly call the Contains(String, StringComparison) overload instead.

using System;

public class Example

{

public static void Main()

{

string str = "techie";

string sub = "Tech";

bool existIgnoreCase = str.Contains(sub, StringComparison.OrdinalIgnoreCase);

Console.WriteLine(existIgnoreCase); // True

}

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Alternatively, you can call ToLower() or ToUpper() method before making case-insensitive searches, as shown below.

using System;

public class Example

{

public static void Main()

{

string str = "techie";

string sub = "Tech";

bool existIgnoreCase = str.ToUpper().Contains(sub.ToUpper());

Console.WriteLine(existIgnoreCase); // True

}

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That’s all about determining whether a string contains a specific substring in C#.

Determine whether a string contains a specific substring in C#

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