boxing/boxing.cs - A program that illustrates boxing and unboxing.

Lecture 4 - slide 15 : 29 Program 1

using System;

public class BoxingTest{
  public static void Main(){
    int i = 15, j, k;
  
    bool b = false, c, d;
    Object obj1 = i,   // boxing of the value of i
           obj2 = b;   // boxing of the value of b
  
    j = (int) obj1;    // unboxing obj1
    c = (bool) obj2;   // unboxing obj2

//  k = i + obj1;    // Compilation error
//  d = b && obj2;   // Compilation error

    k = i + (int)obj1;    
    d = b && (bool)obj2;  
  
    Console.WriteLine("{0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}",
                      i, obj1, b, obj2, j, c, k, d);

  }
}