/*
A Programmer's Introduction to C# (Second Edition)
by Eric Gunnerson
Publisher: Apress L.P.
ISBN: 1-893115-62-3
*/
// 28 - System.Array and the Collection Classes\Sorting and Searching\Overloading Relational Operators
// copyright 2000 Eric Gunnerson
using System;
public class OverloadingRelationalOperators
{
public static void Main()
{
Employee george = new Employee("George", 1);
Employee fred = new Employee("Fred", 2);
Employee tom = new Employee("Tom", 4);
Employee bob = new Employee("Bob", 3);
Console.WriteLine("George < Fred: {0}", george < fred);
Console.WriteLine("Tom >= Bob: {0}", tom >= bob);
}
}
public class Employee: IComparable
{
public Employee(string name, int id)
{
this.name = name;
this.id = id;
}
int IComparable.CompareTo(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.CompareTo (emp2) < 0);
}
public static bool operator >(
Employee emp1,
Employee emp2)
{
IComparable icomp = (IComparable) emp1;
return(icomp.CompareTo (emp2) > 0);
}
public static bool operator <=(
Employee emp1,
Employee emp2)
{
IComparable icomp = (IComparable) emp1;
return(icomp.CompareTo (emp2) <= 0);
}
public static bool operator >=(
Employee emp1,
Employee emp2)
{
IComparable icomp = (IComparable) emp1;
return(icomp.CompareTo (emp2) >= 0);
}
public override string ToString()
{
return(name + ":" + id);
}
string name;
int id;
}
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