Class Interface

illustrates operator overloading

Posted on by coder 

   

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy

Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example7_12.cs illustrates operator overloading
*/

using System;


// declare the Rectangle class
class Rectangle
{

  // declare the fields
  public int width;
  public int height;

  // define constructor
  public Rectangle(int width, int height)
  {
    this.width = width;
    this.height = height;
  }

  // override the ToString() method
  public override string ToString()
  {
    return "width = " + width + ", height = " + height;
  }

  // overload the == operator
  public static bool operator ==(Rectangle lhs, Rectangle rhs)
  {
    Console.WriteLine("In operator ==");
    if (lhs.width == rhs.width && lhs.height == rhs.height)
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  // overload the != operator
  public static bool operator !=(Rectangle lhs, Rectangle rhs)
  {
    Console.WriteLine("In operator !=");
    return !(lhs==rhs);
  }

  // override the Equals() method
  public override bool Equals(object obj)
  {
    Console.WriteLine("In Equals()");
    if (!(obj is Rectangle))
    {
      return false;
    }
    else
    {
      return this == (Rectangle) obj;
    }
  }

  // overload the + operator
  public static Rectangle operator +(Rectangle lhs, Rectangle rhs)
  {
    Console.WriteLine("In operator +");
    return new Rectangle(lhs.width + rhs.width, lhs.height + rhs.height);
  }

}


public class Example7_12
{

  public static void Main()
  {

    // create Rectangle objects
    Rectangle myRectangle = new Rectangle(1, 4);
    Console.WriteLine("myRectangle: " + myRectangle);
    Rectangle myRectangle2 = new Rectangle(1, 4);
    Console.WriteLine("myRectangle2: " + myRectangle2);

    if (myRectangle == myRectangle2)
    {
      Console.WriteLine("myRectangle is equal to myRectangle2");
    }
    else
    {
      Console.WriteLine("myRectangle is not equal to myRectangle2");
    }

    Rectangle myRectangle3 = myRectangle + myRectangle2;
    Console.WriteLine("myRectangle3: " + myRectangle3);

  }

}

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

Posted on by coder 

   

/*
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."); 
  }   
}

Overload true and fase for ThreeD

Posted on by coder 

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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


// Overload true and fase for ThreeD. 
 
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 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; 
  }   
 
  // Overload unary --.  
  public static ThreeD operator --(ThreeD op)  
  {  
    // for ++, modify argument  
    op.x--;  
    op.y--;   
    op.z--;   
  
    return op;  
  }  
 
  // Show X, Y, Z coordinates.   
  public void show()   
  {   
    Console.WriteLine(x + ", " + y + ", " + z);   
  }   
}   
   
public class TrueFalseDemo {   
  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."); 
    else Console.WriteLine("a is false."); 
 
    if(b) Console.WriteLine("b is true."); 
    else Console.WriteLine("b is false."); 
 
    if(c) Console.WriteLine("c is true."); 
    else Console.WriteLine("c is false."); 
 
    Console.WriteLine(); 
 
    Console.WriteLine("Control a loop using a ThreeD object."); 
    do { 
      b.show(); 
      b--; 
    } while(b); 
 
  }   
}

Overload shift operator

Posted on by coder

/*
C#: The Complete Reference
by Herbert Schildt

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

// Overload < and >.

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 <. public static bool operator <(ThreeD op1, ThreeD op2) { if((op1.x < op2.x) && (op1.y < op2.y) && (op1.z < op2.z)) return true; else return false; } // Overload >.
public static bool operator >(ThreeD op1, ThreeD op2)
{
if((op1.x > op2.x) && (op1.y > op2.y) && (op1.z > op2.z))
return true;
else
return false;
}

// Show X, Y, Z coordinates.
public void show()
{
Console.WriteLine(x + “, ” + y + “, ” + z);
}
}

public class ThreeDDemo4 {

public static void Main() {
ThreeD a = new ThreeD(5, 6, 7);
ThreeD b = new ThreeD(10, 10, 10);
ThreeD c = new ThreeD(1, 2, 3);

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 > c) Console.WriteLine(“a > c is true”);
if(a < c) Console.WriteLine("a < c is true"); if(a > b) Console.WriteLine(“a > b is true”);
if(a < b) Console.WriteLine("a < b is true"); } } [/csharp]

Overload the + for object + object, object + int, and int + object

Posted on by coder 

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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


/* Overload the + for object + object, 
   object + int, and int + object. */ 
 
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 binary + for object + object. 
  public static ThreeD operator +(ThreeD op1, ThreeD op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    /* This adds together the coordinates of the two points 
       and returns the result. */ 
    result.x = op1.x + op2.x;  
    result.y = op1.y + op2.y;  
    result.z = op1.z + op2.z;  
 
    return result; 
  } 
 
  // Overload binary + for object + int. 
  public static ThreeD operator +(ThreeD op1, int op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    result.x = op1.x + op2; 
    result.y = op1.y + op2; 
    result.z = op1.z + op2; 
 
    return result; 
  } 
 
  // Overload binary + for int + object. 
  public static ThreeD operator +(int op1, ThreeD op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    result.x = op2.x + op1; 
    result.y = op2.y + op1; 
    result.z = op2.z + op1; 
 
    return result; 
  } 
 
  // Show X, Y, Z coordinates. 
  public void show() 
  { 
    Console.WriteLine(x + ", " + y + ", " + z); 
  } 
} 
 
public class ThreeDDemo3 { 
  public static void Main() { 
    ThreeD a = new ThreeD(1, 2, 3); 
    ThreeD b = new ThreeD(10, 10, 10); 
    ThreeD c = new ThreeD(); 
 
    Console.Write("Here is a: "); 
    a.show(); 
    Console.WriteLine(); 
    Console.Write("Here is b: "); 
    b.show(); 
    Console.WriteLine(); 
 
    c = a + b; // object + object 
    Console.Write("Result of a + b: "); 
    c.show(); 
    Console.WriteLine(); 
 
    c = b + 10; // object + int 
    Console.Write("Result of b + 10: "); 
    c.show(); 
    Console.WriteLine(); 
 
    c = 15 + b; // int + object 
    Console.Write("Result of 15 + b: "); 
    c.show(); 
  } 
}

Overload addition for object + object, and for object + int

Posted on by coder 

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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


/* Overload addition for object + object, and 
   for object + int. */ 
 
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 binary + for object + object. 
  public static ThreeD operator +(ThreeD op1, ThreeD op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    /* This adds together the coordinates of the two points 
       and returns the result. */ 
    result.x = op1.x + op2.x;  
    result.y = op1.y + op2.y;  
    result.z = op1.z + op2.z;  
 
    return result; 
  } 
 
  // Overload binary + for object + int. 
  public static ThreeD operator +(ThreeD op1, int op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    result.x = op1.x + op2; 
    result.y = op1.y + op2; 
    result.z = op1.z + op2; 
 
    return result; 
  } 

  // Show X, Y, Z coordinates. 
  public void show() 
  { 
    Console.WriteLine(x + ", " + y + ", " + z); 
  } 
} 
 
public class ThreeDDemo2 { 
  public static void Main() { 
    ThreeD a = new ThreeD(1, 2, 3); 
    ThreeD b = new ThreeD(10, 10, 10); 
    ThreeD c = new ThreeD(); 
 
    Console.Write("Here is a: "); 
    a.show(); 
    Console.WriteLine(); 
    Console.Write("Here is b: "); 
    b.show(); 
    Console.WriteLine(); 
 
    c = a + b; // object + object 
    Console.Write("Result of a + b: "); 
    c.show(); 
    Console.WriteLine();
 
    c = b + 10; // object + int 
    Console.Write("Result of b + 10: "); 
    c.show(); 
  } 
}

More operator overloading

Posted on by coder 

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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


// More operator overloading. 
 
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 binary +. 
  public static ThreeD operator +(ThreeD op1, ThreeD op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    /* This adds together the coordinates of the two points 
       and returns the result. */ 
    result.x = op1.x + op2.x;  
    result.y = op1.y + op2.y;  
    result.z = op1.z + op2.z;  
 
    return result; 
  } 
 
  // Overload binary -. 
  public static ThreeD operator -(ThreeD op1, ThreeD op2) 
  { 
    ThreeD result = new ThreeD(); 
 
    /* Notice the order of the operands. op1 is the left 
       operand and op2 is the right. */ 
    result.x = op1.x - op2.x;  
    result.y = op1.y - op2.y;  
    result.z = op1.z - op2.z;  
 
    return result; 
  } 
   
  // Overload unary -. 
  public static ThreeD operator -(ThreeD op) 
  { 
    ThreeD result = new ThreeD(); 
 
    result.x = -op.x; 
    result.y = -op.y;  
    result.z = -op.z;  
 
    return result; 
  } 
 
  // Overload unary ++. 
  public static ThreeD operator ++(ThreeD op) 
  { 
    // for ++, modify argument 
    op.x++; 
    op.y++;  
    op.z++;  
 
    return op; 
  } 
 
  // Show X, Y, Z coordinates. 
  public void show() 
  { 
    Console.WriteLine(x + ", " + y + ", " + z); 
  } 
} 
 
public class ThreeDDemo1 { 
  public static void Main() { 
    ThreeD a = new ThreeD(1, 2, 3); 
    ThreeD b = new ThreeD(10, 10, 10); 
    ThreeD c = new ThreeD(); 
 
    Console.Write("Here is a: "); 
    a.show(); 
    Console.WriteLine(); 
    Console.Write("Here is b: "); 
    b.show(); 
    Console.WriteLine(); 
 
    c = a + b; // add a and b together 
    Console.Write("Result of a + b: "); 
    c.show(); 
    Console.WriteLine(); 
 
    c = a + b + c; // add a, b and c together 
    Console.Write("Result of a + b + c: "); 
    c.show(); 
    Console.WriteLine(); 
 
    c = c - a; // subtract a 
    Console.Write("Result of c - a: "); 
    c.show(); 
    Console.WriteLine(); 
 
    c = c - b; // subtract b 
    Console.Write("Result of c - b: "); 
    c.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();   
  } 
}