A better way to overload !, | and & for ThreeD. This version automatically enables the && and || operators

   

/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/


/* A better way to overload !, |, and & for ThreeD. 
   This version automatically enables the && and || operators. */ 
 
using System;   
   
// A three-dimensional coordinate class.   
class ThreeD {   
  int x, y, z; // 3-D coordinates     
   
  public ThreeD() { x = y = z = 0; }   
  public ThreeD(int i, int j, int k) { x = i; y = j; z = k; }   
 
 
  // Overload | for short-circuit evaluation.   
  public static ThreeD operator |(ThreeD op1, ThreeD op2)   
  {  
    if( ((op1.x != 0) || (op1.y != 0) || (op1.z != 0)) | 
       ((op2.x != 0) || (op2.y != 0) || (op2.z != 0)) ) 
      return new ThreeD(1, 1, 1);   
    else   
      return new ThreeD(0, 0, 0);   
  }   
 
  // Overload & for short-circuit evaluation.   
  public static ThreeD operator &(ThreeD op1, ThreeD op2)   
  {   
    if( ((op1.x != 0) && (op1.y != 0) && (op1.z != 0)) & 
       ((op2.x != 0) && (op2.y != 0) && (op2.z != 0)) ) 
      return new ThreeD(1, 1, 1);   
    else   
      return new ThreeD(0, 0, 0);   
  }   
 
  // Overload !.   
  public static bool operator !(ThreeD op)   
  {   
    if(op) return false;   
    else return true;   
  }   
 
  // Overload true.   
  public static bool operator true(ThreeD op) { 
    if((op.x != 0) || (op.y != 0) || (op.z != 0)) 
      return true; // at least one coordinate is non-zero 
    else 
      return false; 
  }   
 
  // Overload false. 
  public static bool operator false(ThreeD op) { 
    if((op.x == 0) && (op.y == 0) && (op.z == 0)) 
      return true; // all coordinates are zero 
    else 
      return false; 
  }   
 
  // Show X, Y, Z coordinates.   
  public void show()   
  {   
    Console.WriteLine(x + ", " + y + ", " + z);   
  }   
}   
   
public class TrueFalseDemo1 {   
  public static void Main() {   
    ThreeD a = new ThreeD(5, 6, 7);   
    ThreeD b = new ThreeD(10, 10, 10);   
    ThreeD c = new ThreeD(0, 0, 0);   
   
    Console.Write("Here is a: ");   
    a.show();   
    Console.Write("Here is b: ");   
    b.show();   
    Console.Write("Here is c: ");   
    c.show();   
    Console.WriteLine();   
   
    if(a) Console.WriteLine("a is true."); 
    if(b) Console.WriteLine("b is true."); 
    if(c) Console.WriteLine("c is true."); 
 
    if(!a) Console.WriteLine("a is false."); 
    if(!b) Console.WriteLine("b is false."); 
    if(!c) Console.WriteLine("c is false."); 
 
    Console.WriteLine(); 
 
    Console.WriteLine("Use & and |"); 
    if(a & b) Console.WriteLine("a & b is true."); 
    else Console.WriteLine("a & b is false."); 
 
    if(a & c) Console.WriteLine("a & c is true."); 
    else Console.WriteLine("a & c is false."); 
 
    if(a | b) Console.WriteLine("a | b is true."); 
    else Console.WriteLine("a | b is false."); 
 
    if(a | c) Console.WriteLine("a | c is true."); 
    else Console.WriteLine("a | c is false."); 
 
    Console.WriteLine(); 
 
    // now use short-circuit ops 
    Console.WriteLine("Use short-circuit && and ||"); 
    if(a && b) Console.WriteLine("a && b is true."); 
    else Console.WriteLine("a && b is false."); 
 
    if(a && c) Console.WriteLine("a && c is true."); 
    else Console.WriteLine("a && c is false."); 
 
    if(a || b) Console.WriteLine("a || b is true."); 
    else Console.WriteLine("a || b is false."); 
 
    if(a || c) Console.WriteLine("a || c is true."); 
    else Console.WriteLine("a || c is false."); 
  }   
}