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SortedList.SetByIndex(Int32, Object) Method

Definition

Replaces the value at a specific index in a SortedList object.

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)

Parameters

index
Int32

The zero-based index at which to save value.

value
Object

The Object to save into the SortedList object. The value can be null.

Exceptions

index is outside the range of valid indexes for the SortedList object.

Examples

The following code example shows how to replace the value of an existing element in a SortedList object.

#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

Remarks

The index sequence is based on the sort sequence. When an element is added, it is inserted into SortedList in the correct sort order, and the indexing adjusts accordingly. When an element is removed, the indexing also adjusts accordingly. Therefore, the index of a specific key/value pair might change as elements are added or removed from the SortedList object.

This method is an O(1) operation.

Applies to

See also