ref keyword in c#

Before calling the method, variables much must be initialized.

Initialization not must inside method.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            swapWithTrd objswap = new swapWithTrd();

            int a = 5;

            int b = 6;

            objswap.swapMethod(ref a, ref b);

            Console.WriteLine("A : " +a +",  B :" +b);

            Console.ReadLine();

        }

    }

    /// <summary>

    /// Swap  using 3rd variable by ref

    /// </summary>

    public class swapWithTrd

    {

        public void swapMethod(ref int a, ref int b)

        {

            a = 40;

            b = 50;

           int temp = a;

           a = b;

           b = temp;

        }

    }

}

/// Out Put:  A: 50, B: 40