C# Regex Double of some letters only - C# Code Example

In C#, regular expressions can be used to manipulate strings by defining patterns that match one or more characters. In this code example, we will be using a regular expression to identify specific letters within a string and double them.

Code Example

Here is an example C# code snippet that demonstrates how to double specific letters in a string using regular expressions:

using System;
using System.Text.RegularExpressions;

class Program
{
    static void Main()
    {
        string input = "This is a sample string.";
        string pattern = "([aeiou])";
        string replacement = "$1$1";

        string result = Regex.Replace(input, pattern, replacement);

        Console.WriteLine("Original String: {0}", input);
        Console.WriteLine("New String: {0}", result);
    }
}

Explanation

• The using statement imports the System and System.Text.RegularExpressions namespaces.

• The Main method sets up a sample string, input, and the regular expression pattern, pattern, and the replacement string, replacement.

• In the regular expression pattern, ([aeiou]) matches any of the letters in the set aeiou and captures it into group 1.

• The replacement string "$1$1" uses the capture group 1 twice to double the matched letters.

• The Regex.Replace method is called with the input, pattern, and replacement strings as arguments. This method returns a new string with all matches replaced.

• The original input string and the new string result are printed to the console.

Output

When you run this code, you should see the following output:

Original String: This is a sample string.
New String: Thhiis is aa saammppllee strinng.

Conclusion

In this code example, we used regular expressions to identify specific letters within a string and double them. Regular expressions can be a powerful tool for manipulating strings in C#.