SortedList.RemoveAt(Int32) 方法

定义

移除 SortedList 对象的指定索引处的元素。Removes the element at the specified index of a SortedList object.

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

待删除元素的从零开始的索引。The zero-based index of the element to remove.

异常

index 不在 SortedList 对象的有效索引范围内。index is outside the range of valid indexes for the SortedList object.

SortedList 为只读。The SortedList is read-only.

- 或 --or- SortedList 具有固定的大小。The SortedList has a fixed size.

示例

下面的代码示例演示如何从 SortedList 对象中移除元素。The following code example shows how to remove elements from a SortedList object.

#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

索引顺序基于排序顺序。The index sequence is based on the sort sequence. 添加元素时,会按正确的顺序将其插入 SortedList 中,并相应地调整索引。When an element is added, it is inserted into SortedList in the correct sort order, and the indexing adjusts accordingly. 删除元素时,索引编制还会相应地进行调整。When an element is removed, the indexing also adjusts accordingly. 因此,在 SortedList 对象中添加或删除元素时,特定键/值对的索引可能会更改。Therefore, the index of a specific key/value pair might change as elements are added or removed from the SortedList object.

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。In collections of contiguous elements, such as lists, the elements that follow the removed element move up to occupy the vacated spot. 如果集合具有索引,则移动的元素的索引也将更新。If the collection is indexed, the indexes of the elements that are moved are also updated. 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。This behavior does not apply to collections where elements are conceptually grouped into buckets, such as a hash table.

此方法是 O(n) 操作,其中 nCount的。This method is an O(n) operation, where n is Count.

适用于

另请参阅