using System;

public class Program

{

    public static void Main()

    {

        //Console.WriteLine("Hello World");

        Test t = new Test();

        t.WriteValue("abc");

    }

}

​

​

public class Test{

    private string teststring = "xyz";

    public void WriteValue(string teststring){

        Console.WriteLine(teststring);

        Console.WriteLine(this.teststring);

    }

}