C#.Net - Scope of a Variable

Variable whose scope covers a single method are known as local variable.

Variable whose scope covers multiple methods are known as global variables. In C#.Net you must use either static or const keyword for declaring a global variable. If you want to modify the value of the global variable, use static, as constant variable prohibits any change in the value of a variable.

Example 1: Local and Global variable.

using System;

namespace ConsoleApplication1
{
    class Program
    {
        //const int a = 10; //global variable
        static int a = 10; //global variable
        static void method()
        {
            int b = 20; //local variable
            Console.WriteLine("Variable inside method = " + a);
        }

        static void Main(string[] args)
        {
            int c = 20; //local variable
			a = 50;
            method();
            Console.WriteLine("Variable inside main method = " + a);
            Console.ReadLine();
        }
    }
}