Csharp/CSharp Tutorial/Operator Overload/Relotional Operator Overload

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Overload > and

using System;  
  
class TwoDimension {  
  int x, y;
  
  public TwoDimension() { 
     x = y = 0; 
  }  
  public TwoDimension(int i, int j) { 
     x = i; 
     y = j;
  }  
  
  // Overload <.  
  public static bool operator <(TwoDimension op1, TwoDimension op2)  
  {  
    if((op1.x < op2.x) && (op1.y < op2.y))  
      return true;  
    else  
      return false;  
  }  
  
  // Overload >.  
  public static bool operator >(TwoDimension op1, TwoDimension op2)  
  {  
    if((op1.x > op2.x) && (op1.y > op2.y))  
      return true;  
    else  
      return false;  
  }  
  
  // Show X, Y
  public void show()  
  {  
    Console.WriteLine(x + ", " + y);  
  }  
}  
  
class TwoDimensionDemo {  
  public static void Main() {  
    TwoDimension a = new TwoDimension(5, 6);  
    TwoDimension b = new TwoDimension(10, 10);  
    TwoDimension c = new TwoDimension(1, 2);  
  
    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");  
  }  
}
Here is a: 5, 6
Here is b: 10, 10
Here is c: 1, 2
a > c is true
a < b is true

Overloading Relational Operators

using System;
public class Employee: IComparable
{
    public Employee(string name, int id)
    {
        this.name = name;
        this.id = id;
    }
    
    int IComparable.rupareTo(object obj)
    {
        Employee emp2 = (Employee) obj;
        if (this.id > emp2.id)
        return(1);
        if (this.id < emp2.id)
        return(-1);
        else
        return(0);
    }
    public static bool operator <(Employee emp1, Employee emp2)
    {
        IComparable icomp = (IComparable) emp1;
        return(icomp.rupareTo (emp2) < 0);
    }
    public static bool operator >(Employee emp1,Employee emp2)
    {
        IComparable    icomp = (IComparable) emp1;
        return(icomp.rupareTo (emp2) > 0);
    }
    public static bool operator <=(Employee emp1,Employee emp2)
    {
        IComparable    icomp = (IComparable) emp1;
        return(icomp.rupareTo (emp2) <= 0);
    }
    public static bool operator >=(Employee emp1,Employee emp2)
    {
        IComparable    icomp = (IComparable) emp1;
        return(icomp.rupareTo (emp2) >= 0);
    }
    
    public override string ToString()
    {
        return(name + ":" + id);
    }
    
    string    name;
    int    id;
}
class Test
{
    public static void Main()
    {
        Employee a = new Employee("A", 1);
        Employee b = new Employee("B", 2);
        Employee c = new Employee("C", 4);
        Employee d = new Employee("D", 3);
        
        Console.WriteLine("a < b: {0}", a < b);
        Console.WriteLine("c >= d: {0}", c >= d);
    }
}
a < b: True
c >= d: True