/*
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.");
}
}
|
