Sorting and Searching:Using IComparer : Compare « Collections Data Structure « C# / C Sharp
Sorting and Searching:Using IComparer
using System;
using System.Collections;
public class SortingandSearchingUsingIComparer1
{
public static void Main()
{
Employee[] arr = new Employee[4];
arr[0] = new Employee("A", 1);
arr[1] = new Employee("B", 2);
arr[2] = new Employee("C", 4);
arr[3] = new Employee("D", 3);
Array.Sort(arr, (IComparer) new Employee.SortByNameClass());
// employees is now sorted by name
foreach (Employee emp in arr)
Console.WriteLine("Employee: {0}", emp);
Array.Sort(arr, (IComparer) new Employee.SortByIdClass());
// employees is now sorted by id
foreach (Employee emp in arr)
Console.WriteLine("Employee: {0}", emp);
ArrayList arrList = new ArrayList();
arrList.Add(arr[0]);
arrList.Add(arr[1]);
arrList.Add(arr[2]);
arrList.Add(arr[3]);
arrList.Sort((IComparer) new Employee.SortByNameClass());
foreach (Employee emp in arrList)
Console.WriteLine("Employee: {0}", emp);
arrList.Sort(); // default is by id
foreach (Employee emp in arrList)
Console.WriteLine("Employee: {0}", emp);
}
}
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 override string ToString()
{
return(name + ":" + id);
}
public class SortByNameClass: IComparer
{
public int Compare(object obj1, object obj2)
{
Employee emp1 = (Employee) obj1;
Employee emp2 = (Employee) obj2;
return(String.Compare(emp1.name, emp2.name));
}
}
public class SortByIdClass: IComparer
{
public int Compare(object obj1, object obj2)
{
Employee emp1 = (Employee) obj1;
Employee emp2 = (Employee) obj2;
return(((IComparable) emp1).CompareTo(obj2));
}
}
string name;
int id;
}
