Boxing and unboxing

Boxing and unboxing is an important concept in C# type system. With Boxing and unboxing one can link between value-types and reference-types by allowing any value of a value-type to be converted to and from type object.

Boxing  

• Boxing is a mechanism in which value type is converted into reference type.
• It is implicit conversion process in which object type (super type) is used.
• In this process type and value both are stored in object type

Unboxing  

• Unboxing is a mechanism in which reference type is converted into value.
• It is explicit conversion process.

Program to show boxing and unboxing:

using System;

namespace boxing

{

    class Program

    {

        static void Main(string[] args)

        {

            int i = 10;

            object o = i;             // boxing

            int j = (int)o;          // unboxing

            Console.WriteLine("value of o object : " + o);

            Console.WriteLine("Value of j : " + j);

            Console.ReadLine();

        }

    }

}