IComparer.Compare(Object, Object) Methode

public:
 int Compare(System::Object ^ x, System::Object ^ y);

public int Compare(object x, object y);

abstract member Compare : obj * obj -> int

Public Function Compare (x As Object, y As Object) As Integer

Parameters

Retouren

Een ondertekend geheel getal dat de relatieve waarden van x en y:
- Als minder dan 0, x kleiner is dan y.
- Als 0, x is gelijk aan y.
- Als groter dan 0, x groter is dan y.

Uitzonderingen

Voorbeelden

In het volgende voorbeeld wordt de IComparer interface gebruikt om een tekenreeksmatrix te sorteren. In dit voorbeeld wordt de Compare methode geïmplementeerd met behulp van de CaseInsensitiveComparer klasse om de volgorde van de inhoud van de matrix om te draaien.

using System;
using System.Collections;

public class Example
{
   public class ReverserClass : IComparer
   {
      // Call CaseInsensitiveComparer.Compare with the parameters reversed.
      int IComparer.Compare(Object x, Object y)
      {
          return ((new CaseInsensitiveComparer()).Compare(y, x));
      }
   }

   public static void Main()
   {
      // Initialize a string array.
      string[] words = { "The", "quick", "brown", "fox", "jumps", "over",
                         "the", "lazy", "dog" };

      // Display the array values.
      Console.WriteLine("The array initially contains the following values:" );
      PrintIndexAndValues(words);

      // Sort the array values using the default comparer.
      Array.Sort(words);
      Console.WriteLine("After sorting with the default comparer:" );
      PrintIndexAndValues(words);

      // Sort the array values using the reverse case-insensitive comparer.
      Array.Sort(words, new ReverserClass());
      Console.WriteLine("After sorting with the reverse case-insensitive comparer:");
      PrintIndexAndValues(words);
   }

   public static void PrintIndexAndValues(IEnumerable list)
   {
      int i = 0;
      foreach (var item in list )
         Console.WriteLine($"   [{i++}]:  {item}");

      Console.WriteLine();
   }
}
// The example displays the following output:
//       The array initially contains the following values:
//          [0]:  The
//          [1]:  quick
//          [2]:  brown
//          [3]:  fox
//          [4]:  jumps
//          [5]:  over
//          [6]:  the
//          [7]:  lazy
//          [8]:  dog
//
//       After sorting with the default comparer:
//          [0]:  brown
//          [1]:  dog
//          [2]:  fox
//          [3]:  jumps
//          [4]:  lazy
//          [5]:  over
//          [6]:  quick
//          [7]:  the
//          [8]:  The
//
//       After sorting with the reverse case-insensitive comparer:
//          [0]:  the
//          [1]:  The
//          [2]:  quick
//          [3]:  over
//          [4]:  lazy
//          [5]:  jumps
//          [6]:  fox
//          [7]:  dog
//          [8]:  brown

Imports System.Collections

Public Class Example
   Public Class ReverserClass : Implements IComparer
      ' Call CaseInsensitiveComparer.Compare with the parameters reversed.
      Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer _
             Implements IComparer.Compare
         Return New CaseInsensitiveComparer().Compare(y, x)
      End Function 
   End Class

   Public Shared Sub Main()
      ' Initialize a string array.
      Dim words() As String = { "The", "quick", "brown", "fox", "jumps", "over",
                         "the", "lazy", "dog" }

      ' Display the array values.
      Console.WriteLine("The array initially contains the following values:")
      PrintIndexAndValues(words)

      ' Sort the array values of the ArrayList using the default comparer.
      Array.Sort(words)
      Console.WriteLine("After sorting with the default comparer:")
      PrintIndexAndValues(words)

      ' Sort the array values using the reverse case-insensitive comparer.
      Array.Sort(words, new ReverserClass())
      Console.WriteLine("After sorting with the reverse case-insensitive comparer:")
      PrintIndexAndValues(words)
   End Sub 

   Public Shared Sub PrintIndexAndValues(list As IEnumerable)
      Dim i As Integer = 0
      For Each item In  list
         Console.WriteLine($"   [{i}]:  {item}")
         i += 1
      Next
      Console.WriteLine()
   End Sub 
End Class
' The example displays the following output:
'       The array initially contains the following values:
'          [0]:  The
'          [1]:  quick
'          [2]:  brown
'          [3]:  fox
'          [4]:  jumps
'          [5]:  over
'          [6]:  the
'          [7]:  lazy
'          [8]:  dog
'       
'       After sorting with the default comparer:
'          [0]:  brown
'          [1]:  dog
'          [2]:  fox
'          [3]:  jumps
'          [4]:  lazy
'          [5]:  over
'          [6]:  quick
'          [7]:  the
'          [8]:  The
'       
'       After sorting with the reverse case-insensitive comparer:
'          [0]:  the
'          [1]:  The
'          [2]:  quick
'          [3]:  over
'          [4]:  lazy
'          [5]:  jumps
'          [6]:  fox
'          [7]:  dog
'          [8]:  brown

Opmerkingen

De voorkeurs implementatie is het gebruik van de CompareTo methode van een van de parameters.

Vergelijking null met elk type is toegestaan en genereert geen uitzondering bij gebruik IComparable. Bij het sorteren null wordt beschouwd als kleiner dan elk ander object.

Zie ook

• IComparable
• CurrentCulture
• CompareInfo
• CultureInfo