SortedList.IndexOfValue(Object) 方法

定义

命名空间:

System.Collections

程序集:

System.Collections.NonGeneric.dll

Source:

SortedList.cs

返回指定的值在 SortedList 对象中第一个匹配项的从零开始的索引。

public:
 virtual int IndexOfValue(System::Object ^ value);

public virtual int IndexOfValue (object? value);

abstract member IndexOfValue : obj -> int
override this.IndexOfValue : obj -> int

Public Overridable Function IndexOfValue (value As Object) As Integer

参数

value

Object

要在 SortedList 对象中定位的值。 该值可以为 null。

返回

Int32

如果在 SortedList 对象中找到 value，则为 value 参数的第一个匹配项的从零开始的索引；否则为 -1。

示例

下面的代码示例演示如何确定对象中 SortedList 键或值的索引。

#using <system.dll>

using namespace System;
using namespace System::Collections;
void PrintIndexAndKeysAndValues( SortedList^ myList )
{
   Console::WriteLine( "\t-INDEX-\t-KEY-\t-VALUE-" );
   for ( int i = 0; i < myList->Count; i++ )
   {
      Console::WriteLine( "\t[{0}]:\t{1}\t{2}", i, myList->GetKey( i ), myList->GetByIndex( i ) );

   }
   Console::WriteLine();
}

int main()
{
   
   // Creates and initializes a new SortedList.
   SortedList^ mySL = gcnew SortedList;
   mySL->Add( 1, "one" );
   mySL->Add( 3, "three" );
   mySL->Add( 2, "two" );
   mySL->Add( 4, "four" );
   mySL->Add( 0, "zero" );
   
   // Displays the values of the SortedList.
   Console::WriteLine( "The SortedList contains the following values:" );
   PrintIndexAndKeysAndValues( mySL );
   
   // Searches for a specific key.
   int myKey = 2;
   Console::WriteLine( "The key \"{0}\" is at index {1}.", myKey, mySL->IndexOfKey( myKey ) );
   
   // Searches for a specific value.
   String^ myValue = "three";
   Console::WriteLine( "The value \"{0}\" is at index {1}.", myValue, mySL->IndexOfValue( myValue ) );
}

/*
This code produces the following output.

The SortedList contains the following values:
        -INDEX- -KEY-   -VALUE-
        [0]:    0       zero
        [1]:    1       one
        [2]:    2       two
        [3]:    3       three
        [4]:    4       four

The key "2" is at index 2.
The value "three" is at index 3.
*/

using System;
using System.Collections;
public class SamplesSortedList  {

   public static void Main()  {

      // Creates and initializes a new SortedList.
      SortedList mySL = new SortedList();
      mySL.Add( 1, "one" );
      mySL.Add( 3, "three" );
      mySL.Add( 2, "two" );
      mySL.Add( 4, "four" );
      mySL.Add( 0, "zero" );

      // Displays the values of the SortedList.
      Console.WriteLine( "The SortedList contains the following values:" );
      PrintIndexAndKeysAndValues( mySL );

      // Searches for a specific key.
      int myKey = 2;
      Console.WriteLine( "The key \"{0}\" is at index {1}.", myKey, mySL.IndexOfKey( myKey ) );

      // Searches for a specific value.
      string myValue = "three";
      Console.WriteLine( "The value \"{0}\" is at index {1}.", myValue, mySL.IndexOfValue( myValue ) );
   }

   public static void PrintIndexAndKeysAndValues( SortedList myList )  {
      Console.WriteLine( "\t-INDEX-\t-KEY-\t-VALUE-" );
      for ( int i = 0; i < myList.Count; i++ )  {
         Console.WriteLine( "\t[{0}]:\t{1}\t{2}", i, myList.GetKey(i), myList.GetByIndex(i) );
      }
      Console.WriteLine();
   }
}
/*
This code produces the following output.

The SortedList contains the following values:
    -INDEX-    -KEY-    -VALUE-
    [0]:    0    zero
    [1]:    1    one
    [2]:    2    two
    [3]:    3    three
    [4]:    4    four

The key "2" is at index 2.
The value "three" is at index 3.
*/

Imports System.Collections

Public Class SamplesSortedList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new SortedList.
        Dim mySL As New SortedList()
        mySL.Add(1, "one")
        mySL.Add(3, "three")
        mySL.Add(2, "two")
        mySL.Add(4, "four")
        mySL.Add(0, "zero")
        
        ' Displays the values of the SortedList.
        Console.WriteLine("The SortedList contains the " & _
           "following values:")
        PrintIndexAndKeysAndValues(mySL)
        
        ' Searches for a specific key.
        Dim myKey As Integer = 2
        Console.WriteLine("The key ""{0}"" is at index {1}.", myKey, _
           mySL.IndexOfKey(myKey))
        
        ' Searches for a specific value.
        Dim myValue As String = "three"
        Console.WriteLine("The value ""{0}"" is at index {1}.", myValue, _
           mySL.IndexOfValue(myValue))
    End Sub    
    
    
    Public Shared Sub PrintIndexAndKeysAndValues(myList As SortedList)
        Console.WriteLine(ControlChars.Tab & "-INDEX-" & ControlChars.Tab & _
           "-KEY-" & ControlChars.Tab & "-VALUE-")
        Dim i As Integer
        For i = 0 To myList.Count - 1
            Console.WriteLine(ControlChars.Tab & "[{0}]:" & ControlChars.Tab & _
               "{1}" & ControlChars.Tab & "{2}", i, myList.GetKey(i), _
               myList.GetByIndex(i))
        Next i
        Console.WriteLine()
    End Sub
End Class

' This code produces the following output.
' 
' The SortedList contains the following values:
'     -INDEX-    -KEY-    -VALUE-
'     [0]:    0    zero
'     [1]:    1    one
'     [2]:    2    two
'     [3]:    3    three
'     [4]:    4    four
'
' The key "2" is at index 2.
' The value "three" is at index 3.

注解

索引序列基于排序序列。 添加元素时，它将按正确的排序顺序插入到 SortedList 中，索引会相应地调整。 删除元素时，索引也会相应地调整。 因此，特定键/值对的索引可能会随着对象中的 SortedList 添加或删除元素而更改。

使用 Equals 方法将 的 SortedList 元素的值与指定的值进行比较。

此方法使用线性搜索;因此，此方法是一个 O(n) 操作，其中 n 为 Count。

从 .NET Framework 2.0 开始，此方法使用集合的对象 Equals 和 CompareTo 方法item来确定项是否存在。 在早期版本的.NET Framework中，此确定是通过对集合中的 对象使用 Equals 参数的 item 和 CompareTo 方法进行的。

另请参阅

• ContainsValue(Object)
• IndexOfKey(Object)
• 在集合中执行不区分区域性的字符串操作