SortedList.TrimToSize Metoda

  • Odwołanie

Definicja

Przestrzeń nazw:
System.Collections
Zestawy:
mscorlib.dll, System.Collections.NonGeneric.dll
Zestaw:
System.Collections.NonGeneric.dll
Zestaw:
mscorlib.dll
Zestaw:
netstandard.dll
Źródło:
SortedList.cs
Źródło:
SortedList.cs
Źródło:
SortedList.cs

Ustawia pojemność na rzeczywistą liczbę elementów w SortedList obiekcie.

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

Wyjątki

NotSupportedException

Obiekt SortedList jest tylko do odczytu.

-lub-

Element SortedList ma stały rozmiar.

Przykłady

Poniższy przykład kodu pokazuje, jak przyciąć nieużywane części SortedList obiektu i jak wyczyścić jego wartości.

#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-

Uwagi

Tej metody można użyć do zminimalizowania obciążenia pamięci kolekcji, jeśli do kolekcji nie zostaną dodane żadne nowe elementy.

Aby zresetować obiekt do stanu początkowegoSortedList, przed wywołaniem metody TrimToSizewywołaj metodę Clear . Przycinanie pustej SortedList wartości powoduje ustawienie pojemności SortedList domyślnej.

Ta metoda jest operacją O(n) , gdzie n to Count.

Dotyczy

Zobacz też