关于ArrayList的排序

1.微软的例子

using System;
using System.Collections;

public class SamplesArrayList  {
 
   public class myReverserClass : IComparer  {

      // Calls CaseInsensitiveComparer.Compare with the parameters reversed.
      int IComparer.Compare( Object x, Object y )  {
          return( (new CaseInsensitiveComparer()).Compare( y, x ) );
      }

   }

   public static void Main()  {
 
      // Creates and initializes a new ArrayList.
      ArrayList myAL = new ArrayList();
      myAL.Add( "The" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );
 
      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList initially contains the following values:" );
      PrintIndexAndValues( myAL );
 
      // Sorts the values of the ArrayList using the default comparer.
      myAL.Sort();
      Console.WriteLine( "After sorting with the default comparer:" );
      PrintIndexAndValues( myAL );

      // Sorts the values of the ArrayList using the reverse case-insensitive comparer.
      IComparer myComparer = new myReverserClass();
      myAL.Sort( myComparer );
      Console.WriteLine( "After sorting with the reverse case-insensitive comparer:" );
      PrintIndexAndValues( myAL );

   }
 
   public static void PrintIndexAndValues( IEnumerable myList )  {
      int i = 0;
      foreach ( Object obj in myList )
         Console.WriteLine( "\t[{0}]:\t{1}", i++, obj );
      Console.WriteLine();
   }

}

 

2.修改自网上的例子

using System;
using System.Collections;

class Employee{
   public string name;
   public int age;
   public string sex;
   public string id;
}

class EmployeeCompareAge:System.Collections.IComparer {
   public int Compare(object x,object y)
   {
      return ((Employee)x).age-((Employee)y).age;
   }
}

class EmployeeCompareId:System.Collections.IComparer {
   public int Compare(object x,object y)
   {
      string strSortX=(x as Employee).id;
      string strSortY=(y as Employee).id;
      
      strSortX=strSortX.Substring(strSortX.Length-3);
      strSortY=strSortY.Substring(strSortY.Length-3);

      //Console.WriteLine(strSortX);
      //Console.WriteLine(strSortY);

      return strSortX.CompareTo(strSortY);
   }
}

class Example
{
    public static void Main()
    {
        Employee ep1=new Employee();
        ep1.name="小白";
        ep1.age=21;
        ep1.sex="男";
        ep1.id="M003";
        
        Employee ep2=new Employee();
        ep2.name="小黑";
        ep2.age=43;
        ep2.sex="男";
        ep2.id="M001";
        
        Employee ep3=new Employee();
        ep3.name="小红";
        ep3.age=18;
        ep3.sex="女";
        ep3.id="F002";

        ArrayList EmployeeList=new ArrayList();
        EmployeeList.Add(ep1);
        EmployeeList.Add(ep2);
        EmployeeList.Add(ep3);

        //按年龄排序
        EmployeeCompareAge EmployeeCmpAge=new EmployeeCompareAge();
        EmployeeList.Sort(EmployeeCmpAge);
        PrintIndexAndValues(EmployeeList);

        //按编号后三位排序
        EmployeeCompareId EmployeeCmpId=new EmployeeCompareId();
        EmployeeList.Sort(EmployeeCmpId);
        PrintIndexAndValues(EmployeeList);
        //Console.WriteLine();
    }

    public static void PrintIndexAndValues(IEnumerable myList)  {
      int i = 0;
      Console.WriteLine("=====================");
      foreach (Object obj in myList)
         Console.WriteLine( "\t[{0}]:\t{1}", i++, (obj as Employee).name );      
   }
}