//https://www.c-sharpcorner.com/blogs/what-is-optional-arguments-in-c-sharp

​

using System;  

namespace Tutpoint  

{  

    public class Program  

    {  

        public static void Main(string[] args)  

        {  

            Console.WriteLine("hello Tutpoint");  

            ///Call the method by omiting Optional Arguments  

            Program.Details(1,"Shubham");  

            ///Call the method by omiting 'course' Optional Arguments  

            Program.Details(2, "Rishabh", 11);

            ///Call the method with all the parameters that will override the default values  

            Program.Details(3, "Anuj", 12, "Art");

        }  

        ///Method used to write students details with parameters as roll_No,name,id and course.  

        ///Here parameter id and course have been assigned with a default value, so these are the Optional Arguments  

        public static void Details(int roll_No, string name, int id=10, string course="Btech" )  

        {  

            Console.WriteLine(string.Format("Roll No.: {0}, Name: {1}, id: {2}, Course: {3}",roll_No,name,id,course));  

        }  

    }    

}