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SortedList.SetByIndex(Int32, Object) Metodo

Definizione

Sostituisce il valore in corrispondenza di un indice specifico in un oggetto SortedList.

public:
 virtual void SetByIndex(int index, System::Object ^ value);
public virtual void SetByIndex (int index, object value);
public virtual void SetByIndex (int index, object? value);
abstract member SetByIndex : int * obj -> unit
override this.SetByIndex : int * obj -> unit
Public Overridable Sub SetByIndex (index As Integer, value As Object)

Parametri

index
Int32

Indice in base zero nel quale salvare value.

value
Object

Oggetto Object da salvare nell'oggetto SortedList. Il valore può essere null.

Eccezioni

Il parametro index non rientra nell'intervallo di indici validi per l'oggetto SortedList.

Esempio

Nell'esempio di codice seguente viene illustrato come sostituire il valore di un elemento esistente in un SortedList oggetto .

#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( 2, "two" );
   mySL->Add( 3, "three" );
   mySL->Add( 1, "one" );
   mySL->Add( 0, "zero" );
   mySL->Add( 4, "four" );
   
   // Displays the values of the SortedList.
   Console::WriteLine( "The SortedList contains the following values:" );
   PrintIndexAndKeysAndValues( mySL );
   
   // Replaces the values at index 3 and index 4.
   mySL->SetByIndex( 3, "III" );
   mySL->SetByIndex( 4, "IV" );
   
   // Displays the updated values of the SortedList.
   Console::WriteLine( "After replacing the value at index 3 and index 4," );
   PrintIndexAndKeysAndValues( mySL );
}

/*
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

After replacing the value at index 3 and index 4,
        -INDEX- -KEY-   -VALUE-
        [0]:    0       zero
        [1]:    1       one
        [2]:    2       two
        [3]:    3       III
        [4]:    4       IV
*/
using System;
using System.Collections;
public class SamplesSortedList  {

   public static void Main()  {

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

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

      // Replaces the values at index 3 and index 4.
      mySL.SetByIndex( 3, "III" );
      mySL.SetByIndex( 4, "IV" );

      // Displays the updated values of the SortedList.
      Console.WriteLine( "After replacing the value at index 3 and index 4," );
      PrintIndexAndKeysAndValues( mySL );
   }

   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

After replacing the value at index 3 and index 4,
    -INDEX-    -KEY-    -VALUE-
    [0]:    0    zero
    [1]:    1    one
    [2]:    2    two
    [3]:    3    III
    [4]:    4    IV
*/
Imports System.Collections

Public Class SamplesSortedList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new SortedList.
        Dim mySL As New SortedList()
        mySL.Add(2, "two")
        mySL.Add(3, "three")
        mySL.Add(1, "one")
        mySL.Add(0, "zero")
        mySL.Add(4, "four")
        
        ' Displays the values of the SortedList.
        Console.WriteLine("The SortedList contains the following" & _
           "values:")
        PrintIndexAndKeysAndValues(mySL)
        
        ' Replaces the values at index 3 and index 4.
        mySL.SetByIndex(3, "III")
        mySL.SetByIndex(4, "IV")
        
        ' Displays the updated values of the SortedList.
        Console.WriteLine("After replacing the value at index 3 and index 4,")
        PrintIndexAndKeysAndValues(mySL)
    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
' 
' After replacing the value at index 3 and index 4,
'     -INDEX-    -KEY-    -VALUE-
'     [0]:    0    zero
'     [1]:    1    one
'     [2]:    2    two
'     [3]:    3    III
'     [4]:    4    IV

Commenti

La sequenza di indice è basata sulla sequenza di ordinamento. Quando viene aggiunto un elemento, viene inserito nell'ordinamento SortedList corretto e l'indicizzazione viene modificata di conseguenza. Quando un elemento viene rimosso, anche l'indicizzazione viene modificata di conseguenza. Di conseguenza, l'indice di una coppia chiave/valore specifica può cambiare man mano che gli elementi vengono aggiunti o rimossi dall'oggetto SortedList .

Questo metodo è un'operazione O(1) .

Si applica a

Vedi anche