Wednesday, 18 February 2015

This post demonstrates how to define your own operators by using user-defined classes that can overload operators .
Operator overloading allows user to define own operator implementations to be specified for operations where the operands are of user-defined or struct type, thus changing their meaning when applied.

The following example changes the behaviour of built-in addition operator. Let name this user-defined operator as “Complex Addition”. Consider a complex number, num = 2+3i, where 2 is a real part and 3i is an imaginary part. So the complex addition operator sums the real parts and imaginary parts of two complex numbers.

Code -

// complex.cs
using System;

public struct Complex
{
public int real;
public int imaginary;

//parametrized constructor
public Complex(int real, int imaginary)
{
this.real = real;
this.imaginary = imaginary;
}

// Declare which operator to overload (+), the types
// that can be added (two Complex objects), and the
// return type (Complex):
public static Complex operator +(Complex c1, Complex c2)
{
return new Complex(c1.real + c2.real, c1.imaginary + c2.imaginary);
}
// Override the ToString method to display an complex number in the suitable format:
public override string ToString()
{
return(String.Format("{0} + {1}i", real, imaginary));
}

public static void Main()
{
Complex num1 = new Complex(2, 3);
Complex num2 = new Complex(3, 4);

// Add two Complex objects (num1 and num2) through the
// overloaded plus operator:
Complex sum = num1 + num2;

// Print the numbers and the sum using the overriden ToString method:
Console.WriteLine("First complex number:  {0}", num1);
Console.WriteLine("Second complex number: {0}", num2);
Console.WriteLine("The sum of the two numbers: {0}", sum);

}
}
/* output:
First complex number:  2 + 3i
Second complex number: 3 + 4i
The sum of the two numbers: 5 + 7i
*/

Please share your thoughts on this post in the comments section. Karthik Byggari

Author & Editor

Computer Science graduate, Techie, Founder of logicallyproven, Love to Share and Read About pprogramming related things. 