SortedList.TrimToSize 方法

定义

将容量设置为 SortedList 对象中元素的实际数目。Sets the capacity to the actual number of elements in a SortedList object.

public:
 virtual void TrimToSize();
public virtual void TrimToSize ();
abstract member TrimToSize : unit -> unit
override this.TrimToSize : unit -> unit
Public Overridable Sub TrimToSize ()

异常

SortedList 对象是只读的。The SortedList object 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剪裁 SortedList 对象的未使用部分以及如何清除其值。The following code example shows how to trim the unused portions of a SortedList object and how to clear its values.

#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( "one", "The" );
   mySL->Add( "two", "quick" );
   mySL->Add( "three", "brown" );
   mySL->Add( "four", "fox" );
   mySL->Add( "five", "jumps" );
   
   // Displays the count, capacity and values of the SortedList.
   Console::WriteLine(  "Initially," );
   Console::WriteLine(  "   Count    : {0}", mySL->Count );
   Console::WriteLine(  "   Capacity : {0}", mySL->Capacity );
   Console::WriteLine(  "   Values:" );
   PrintKeysAndValues( mySL );
   
   // Trims the SortedList.
   mySL->TrimToSize();
   
   // Displays the count, capacity and values of the SortedList.
   Console::WriteLine(  "After TrimToSize," );
   Console::WriteLine(  "   Count    : {0}", mySL->Count );
   Console::WriteLine(  "   Capacity : {0}", mySL->Capacity );
   Console::WriteLine(  "   Values:" );
   PrintKeysAndValues( mySL );
   
   // Clears the SortedList.
   mySL->Clear();
   
   // Displays the count, capacity and values of the SortedList.
   Console::WriteLine(  "After Clear," );
   Console::WriteLine(  "   Count    : {0}", mySL->Count );
   Console::WriteLine(  "   Capacity : {0}", mySL->Capacity );
   Console::WriteLine(  "   Values:" );
   PrintKeysAndValues( mySL );
   
   // Trims the SortedList again.
   mySL->TrimToSize();
   
   // Displays the count, capacity and values of the SortedList.
   Console::WriteLine(  "After the second TrimToSize," );
   Console::WriteLine(  "   Count    : {0}", mySL->Count );
   Console::WriteLine(  "   Capacity : {0}", mySL->Capacity );
   Console::WriteLine(  "   Values:" );
   PrintKeysAndValues( mySL );
}

/* 
This code produces the following output.

Initially,
   Count    : 5
   Capacity : 16
   Values:
        -KEY-   -VALUE-
        five:   jumps
        four:   fox
        one:    The
        three:  brown
        two:    quick

After TrimToSize,
   Count    : 5
   Capacity : 5
   Values:
        -KEY-   -VALUE-
        five:   jumps
        four:   fox
        one:    The
        three:  brown
        two:    quick

After Clear,
   Count    : 0
   Capacity : 16
   Values:
        -KEY-   -VALUE-

After the second TrimToSize,
   Count    : 0
   Capacity : 16
   Values:
        -KEY-   -VALUE-

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

   public static void Main()  {

      // Creates and initializes a new SortedList.
      SortedList mySL = new SortedList();
      mySL.Add( "one", "The" );
      mySL.Add( "two", "quick" );
      mySL.Add( "three", "brown" );
      mySL.Add( "four", "fox" );
      mySL.Add( "five", "jumps" );

      // Displays the count, capacity and values of the SortedList.
      Console.WriteLine( "Initially," );
      Console.WriteLine( "   Count    : {0}", mySL.Count );
      Console.WriteLine( "   Capacity : {0}", mySL.Capacity );
      Console.WriteLine( "   Values:" );
      PrintKeysAndValues( mySL );

      // Trims the SortedList.
      mySL.TrimToSize();

      // Displays the count, capacity and values of the SortedList.
      Console.WriteLine( "After TrimToSize," );
      Console.WriteLine( "   Count    : {0}", mySL.Count );
      Console.WriteLine( "   Capacity : {0}", mySL.Capacity );
      Console.WriteLine( "   Values:" );
      PrintKeysAndValues( mySL );

      // Clears the SortedList.
      mySL.Clear();

      // Displays the count, capacity and values of the SortedList.
      Console.WriteLine( "After Clear," );
      Console.WriteLine( "   Count    : {0}", mySL.Count );
      Console.WriteLine( "   Capacity : {0}", mySL.Capacity );
      Console.WriteLine( "   Values:" );
      PrintKeysAndValues( mySL );

      // Trims the SortedList again.
      mySL.TrimToSize();

      // Displays the count, capacity and values of the SortedList.
      Console.WriteLine( "After the second TrimToSize," );
      Console.WriteLine( "   Count    : {0}", mySL.Count );
      Console.WriteLine( "   Capacity : {0}", mySL.Capacity );
      Console.WriteLine( "   Values:" );
      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.

Initially,
   Count    : 5
   Capacity : 16
   Values:
    -KEY-    -VALUE-
    five:    jumps
    four:    fox
    one:    The
    three:    brown
    two:    quick

After TrimToSize,
   Count    : 5
   Capacity : 5
   Values:
    -KEY-    -VALUE-
    five:    jumps
    four:    fox
    one:    The
    three:    brown
    two:    quick

After Clear,
   Count    : 0
   Capacity : 16
   Values:
    -KEY-    -VALUE-

After the second TrimToSize,
   Count    : 0
   Capacity : 16
   Values:
    -KEY-    -VALUE-
*/ 
Imports System.Collections

Public Class SamplesSortedList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new SortedList.
        Dim mySL As New SortedList()
        mySL.Add("one", "The")
        mySL.Add("two", "quick")
        mySL.Add("three", "brown")
        mySL.Add("four", "fox")
        mySL.Add("five", "jumps")
        
        ' Displays the count, capacity and values of the SortedList.
        Console.WriteLine("Initially,")
        Console.WriteLine("   Count    : {0}", mySL.Count)
        Console.WriteLine("   Capacity : {0}", mySL.Capacity)
        Console.WriteLine("   Values:")
        PrintKeysAndValues(mySL)
        
        ' Trims the SortedList.
        mySL.TrimToSize()
        
        ' Displays the count, capacity and values of the SortedList.
        Console.WriteLine("After TrimToSize,")
        Console.WriteLine("   Count    : {0}", mySL.Count)
        Console.WriteLine("   Capacity : {0}", mySL.Capacity)
        Console.WriteLine("   Values:")
        PrintKeysAndValues(mySL)
        
        ' Clears the SortedList.
        mySL.Clear()
        
        ' Displays the count, capacity and values of the SortedList.
        Console.WriteLine("After Clear,")
        Console.WriteLine("   Count    : {0}", mySL.Count)
        Console.WriteLine("   Capacity : {0}", mySL.Capacity)
        Console.WriteLine("   Values:")
        PrintKeysAndValues(mySL)
        
        ' Trims the SortedList again.
        mySL.TrimToSize()
        
        ' Displays the count, capacity and values of the SortedList.
        Console.WriteLine("After the second TrimToSize,")
        Console.WriteLine("   Count    : {0}", mySL.Count)
        Console.WriteLine("   Capacity : {0}", mySL.Capacity)
        Console.WriteLine("   Values:")
        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.
' 
' Initially,
'    Count    : 5
'    Capacity : 16
'    Values:
'     -KEY-    -VALUE-
'     five:    jumps
'     four:    fox
'     one:    The
'     three:    brown
'     two:    quick
'
' After TrimToSize,
'    Count    : 5
'    Capacity : 5
'    Values:
'     -KEY-    -VALUE-
'     five:    jumps
'     four:    fox
'     one:    The
'     three:    brown
'     two:    quick
' 
' After Clear,
'    Count    : 0
'    Capacity : 16
'    Values:
'     -KEY-    -VALUE-
' 
'
' After the second TrimToSize,
'    Count    : 0
'    Capacity : 16
'    Values:
'     -KEY-    -VALUE-
 

注解

如果没有新元素添加到集合中,则可以使用此方法最大程度地减少集合的内存开销。This method can be used to minimize a collection's memory overhead if no new elements will be added to the collection.

若要将 SortedList 对象重置为其初始状态,请在调用 TrimToSize之前调用 Clear 方法。To reset a SortedList object to its initial state, call the Clear method before calling TrimToSize. 修整空 SortedList 会将 SortedList 的容量设置为默认容量。Trimming an empty SortedList sets the capacity of the SortedList to the default capacity.

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