SortedList.RemoveAt(Int32) 方法

定义

移除 SortedList 对象的指定索引处的元素。

public:
 virtual void RemoveAt(int index);
public virtual void RemoveAt (int index);
abstract member RemoveAt : int -> unit
override this.RemoveAt : int -> unit
Public Overridable Sub RemoveAt (index As Integer)

参数

index
Int32

要移除的元素的从零开始的索引。

例外

index 不在 SortedList 对象的有效索引范围内。

SortedList 为只读。

- 或 -

SortedList 具有固定的大小。

示例

下面的代码示例演示如何从 SortedList 对象中删除元素。

#using <system.dll>

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

   }
   Console::WriteLine();
}

int main()
{
   
   // Creates and initializes a new SortedList.
   SortedList^ mySL = gcnew SortedList;
   mySL->Add( "3c", "dog" );
   mySL->Add( "2c", "over" );
   mySL->Add( "1c", "brown" );
   mySL->Add( "1a", "The" );
   mySL->Add( "1b", "quick" );
   mySL->Add( "3a", "the" );
   mySL->Add( "3b", "lazy" );
   mySL->Add( "2a", "fox" );
   mySL->Add( "2b", "jumps" );
   
   // Displays the SortedList.
   Console::WriteLine( "The SortedList initially contains the following:" );
   PrintKeysAndValues( mySL );
   
   // Removes the element with the key "3b".
   mySL->Remove( "3b" );
   
   // Displays the current state of the SortedList.
   Console::WriteLine( "After removing \"lazy\":" );
   PrintKeysAndValues( mySL );
   
   // Removes the element at index 5.
   mySL->RemoveAt( 5 );
   
   // Displays the current state of the SortedList.
   Console::WriteLine( "After removing the element at index 5:" );
   PrintKeysAndValues( mySL );
}

/*
This code produces the following output.

The SortedList initially contains the following:
        -KEY-   -VALUE-
        1a:     The
        1b:     quick
        1c:     brown
        2a:     fox
        2b:     jumps
        2c:     over
        3a:     the
        3b:     lazy
        3c:     dog

After removing "lazy":
        -KEY-   -VALUE-
        1a:     The
        1b:     quick
        1c:     brown
        2a:     fox
        2b:     jumps
        2c:     over
        3a:     the
        3c:     dog

After removing the element at index 5:
        -KEY-   -VALUE-
        1a:     The
        1b:     quick
        1c:     brown
        2a:     fox
        2b:     jumps
        3a:     the
        3c:     dog
*/
using System;
using System.Collections;
public class SamplesSortedList  {

   public static void Main()  {

      // Creates and initializes a new SortedList.
      SortedList mySL = new SortedList();
      mySL.Add( "3c", "dog" );
      mySL.Add( "2c", "over" );
      mySL.Add( "1c", "brown" );
      mySL.Add( "1a", "The" );
      mySL.Add( "1b", "quick" );
      mySL.Add( "3a", "the" );
      mySL.Add( "3b", "lazy" );
      mySL.Add( "2a", "fox" );
      mySL.Add( "2b", "jumps" );

      // Displays the SortedList.
      Console.WriteLine( "The SortedList initially contains the following:" );
      PrintKeysAndValues( mySL );

      // Removes the element with the key "3b".
      mySL.Remove( "3b" );

      // Displays the current state of the SortedList.
      Console.WriteLine( "After removing \"lazy\":" );
      PrintKeysAndValues( mySL );

      // Removes the element at index 5.
      mySL.RemoveAt( 5 );

      // Displays the current state of the SortedList.
      Console.WriteLine( "After removing the element at index 5:" );
      PrintKeysAndValues( mySL );
   }

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

The SortedList initially contains the following:
    -KEY-    -VALUE-
    1a:    The
    1b:    quick
    1c:    brown
    2a:    fox
    2b:    jumps
    2c:    over
    3a:    the
    3b:    lazy
    3c:    dog

After removing "lazy":
    -KEY-    -VALUE-
    1a:    The
    1b:    quick
    1c:    brown
    2a:    fox
    2b:    jumps
    2c:    over
    3a:    the
    3c:    dog

After removing the element at index 5:
    -KEY-    -VALUE-
    1a:    The
    1b:    quick
    1c:    brown
    2a:    fox
    2b:    jumps
    3a:    the
    3c:    dog
*/
Imports System.Collections

Public Class SamplesSortedList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new SortedList.
        Dim mySL As New SortedList()
        mySL.Add("3c", "dog")
        mySL.Add("2c", "over")
        mySL.Add("1c", "brown")
        mySL.Add("1a", "The")
        mySL.Add("1b", "quick")
        mySL.Add("3a", "the")
        mySL.Add("3b", "lazy")
        mySL.Add("2a", "fox")
        mySL.Add("2b", "jumps")
        
        ' Displays the SortedList.
        Console.WriteLine("The SortedList initially contains the following:")
        PrintKeysAndValues(mySL)
        
        ' Removes the element with the key "3b".
        mySL.Remove("3b")
        
        ' Displays the current state of the SortedList.
        Console.WriteLine("After removing ""lazy"":")
        PrintKeysAndValues(mySL)
        
        ' Removes the element at index 5.
        mySL.RemoveAt(5)
        
        ' Displays the current state of the SortedList.
        Console.WriteLine("After removing the element at index 5:")
        PrintKeysAndValues(mySL)
    End Sub
    
    
    Public Shared Sub PrintKeysAndValues(myList As SortedList)
        Console.WriteLine(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}", myList.GetKey(i), myList.GetByIndex(i))
        Next i
        Console.WriteLine()
    End Sub
End Class

' This code produces the following output.
' 
' The SortedList initially contains the following:
'     -KEY-    -VALUE-
'     1a:    The
'     1b:    quick
'     1c:    brown
'     2a:    fox
'     2b:    jumps
'     2c:    over
'     3a:    the
'     3b:    lazy
'     3c:    dog
' 
' After removing "lazy":
'     -KEY-    -VALUE-
'     1a:    The
'     1b:    quick
'     1c:    brown
'     2a:    fox
'     2b:    jumps
'     2c:    over
'     3a:    the
'     3c:    dog
' 
' After removing the element at index 5:
'     -KEY-    -VALUE-
'     1a:    The
'     1b:    quick
'     1c:    brown
'     2a:    fox
'     2b:    jumps
'     3a:    the
'     3c:    dog

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,索引也会相应地进行调整。 因此,在对象中添加或移除元素时,特定键/值对的 SortedList 索引可能会更改。

在由连续的元素组成的集合(如列表)中,已移除元素下面的元素将上移以占据空出的位置。 如果集合具有索引,则移动的元素的索引也将更新。 此行为不适用于元素按概念划分为不同存储桶的集合,如哈希表。

此方法是一个 O(n) 操作,其中 nCount

适用于

另请参阅