Csharp/CSharp Tutorial/Operator Overload/unary minus plusplus

Overload unary - and ++

<source lang="csharp">using System;

class TwoDimension {

 int x, y;

 public TwoDimension() { 
    x = y = 0; 
 } 
 public TwoDimension(int i, int j) { 
    x = i; 
    y = j;
 } 

 // Overload unary -. 
 public static TwoDimension operator -(TwoDimension op) 
 { 
   TwoDimension result = new TwoDimension(); 

   result.x = -op.x; 
   result.y = -op.y;  

   return result; 
 } 

 // Overload unary ++. 
 public static TwoDimension operator ++(TwoDimension op) 
 { 
   // for ++, modify argument 
   op.x++; 
   op.y++;  

   return op; 
 } 

 // Show X, Y 
 public void show() 
 { 
   Console.WriteLine(x + ", " + y); 
 } 

}

class MainClass {

 public static void Main() { 
   TwoDimension a = new TwoDimension(1, 2); 
   TwoDimension b = new TwoDimension(10, 10); 
   TwoDimension c = new TwoDimension(); 

   Console.Write("Here is a: "); 
   a.show(); 
   Console.WriteLine(); 
   Console.Write("Here is b: "); 
   b.show(); 
   Console.WriteLine(); 

   c = -a; // assign -a to c 
   Console.Write("Result of -a: "); 
   c.show(); 
   Console.WriteLine(); 

   a++; // increment a 
   Console.Write("Result of a++: "); 
   a.show();   
 } 

}</source>

Here is a: 1, 2
Here is b: 10, 10
Result of -a: -1, -2
Result of a++: 2, 3