Consider the program:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main()
        {
            String str1 = "  This is a sample string  "; ;
            String str2;
           
            str2 = str1.TrimEnd();

            Console.WriteLine("Trimmed string is:(" + str2+")");

        }
    }
  
}

Output

Trimmed string is:(  This is a sample string)

Note: Input string contains spaces at starting and ending but String.TrimEnd() removes ending (trailing) spaces only.