IComparer 介面
定義
公開比較兩個物件的方法。Exposes a method that compares two objects.
public interface class IComparer
public interface IComparer
[System.Runtime.InteropServices.ComVisible(true)]
public interface IComparer
type IComparer = interface
[<System.Runtime.InteropServices.ComVisible(true)>]
type IComparer = interface
Public Interface IComparer
- 衍生
- 屬性
範例
下列範例會使用 IComparer 介面來排序字串陣列。The following example uses the IComparer interface to sort a string array. 在此範例中, Compare 會使用類別來執行方法, CaseInsensitiveComparer 以反轉陣列內容的順序。In this example, the Compare method is implemented using the CaseInsensitiveComparer class to reverse the order of the contents of the array.
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
備註
這個介面是與和方法搭配使用 Array.Sort Array.BinarySearch 。This interface is used in conjunction with the Array.Sort and Array.BinarySearch methods. 它提供一種方式,可自訂集合的排序次序。It provides a way to customize the sort order of a collection. 請參閱關於 Compare 參數和傳回值的附注方法。See the Compare method for notes on parameters and return value. 它的泛型對等專案是 System.Collections.Generic.IComparer<T> 介面。Its generic equivalent is the System.Collections.Generic.IComparer<T> interface.
此介面的預設實作為 Comparer 類別。The default implementation of this interface is the Comparer class. 如需此介面的泛型版本,請參閱 System.Collections.Generic.IComparer<T> 。For the generic version of this interface, see System.Collections.Generic.IComparer<T>.
方法
Compare(Object, Object) |
比較兩個物件並傳回值,指出其中一個物件為小於、等於或大於另一個物件。Compares two objects and returns a value indicating whether one is less than, equal to, or greater than the other. |