Right

Often we need just the rightmost few characters in a C# string. We can implement Right() as a custom extension method. It returns the right part as a new string.

There is no Right() in .NET. But we can add one with extension method syntax. This helps us translate programs from other languages that have Right.

Input and output

Suppose we pass in the string "orange cat" and want just the right 3 characters. The word "cat" should be returned by Right().

Input:    "orange cat"
Right(3): "cat"

Example code

This program implements Right() using the extension method syntax. Right is called on a string. It internally returns a substring of the rightmost several characters.

using System;

static class Extensions
{
    /// <summary>
    /// Get substring of specified number of characters on the right.
    /// </summary>
    public static string Right(this string value, int length)
    {
        return value.Substring(value.Length - length);
    }
}

class Program
{
    static void Main()
    {
        const string value1 = "orange cat";
        const string value2 = "PERLS";
        string result1 = value1.Right(3);
        string result2 = value2.Right(1);
        Console.WriteLine(result1);
        Console.WriteLine(result2);
    }
}
cat
S

Exceptions

The exceptions thrown by the Right extension are similar to those thrown by the Substring method. Substring will be the source of the exceptions.

Right returns a string instance containing the specified number of characters starting from the final character index. The Right method is not built into the .NET string type.