ListBox.SetSelected(Int32, Boolean) Méthode

Définition

Sélectionne ou efface la sélection pour l'élément spécifié dans ListBox.Selects or clears the selection for the specified item in a ListBox.

public:
 void SetSelected(int index, bool value);
public void SetSelected (int index, bool value);
member this.SetSelected : int * bool -> unit
Public Sub SetSelected (index As Integer, value As Boolean)

Paramètres

index
Int32

Index de base zéro de l'élément dans un ListBox à sélectionner ou désélectionner.The zero-based index of the item in a ListBox to select or clear the selection for.

value
Boolean

true pour sélectionner l'élément spécifié ; sinon, false.true to select the specified item; otherwise, false.

Exceptions

L'index spécifié n'est pas dans l'intervalle des valeurs valides.The specified index was outside the range of valid values.

La propriété SelectionMode a la valeur None.The SelectionMode property was set to None.

Exemples

L’exemple de code suivant montre comment créer un contrôle ListBox qui affiche plusieurs éléments dans des colonnes et peut avoir plusieurs éléments sélectionnés dans la liste du contrôle.The following code example demonstrates how to create a ListBox control that displays multiple items in columns and can have more than one item selected in the control's list. Le code de l’exemple ajoute 50 éléments à la ListBox à l’aide de la méthode Add de la classe ListBox.ObjectCollection, puis sélectionne trois éléments dans la liste à l’aide de la méthode SetSelected.The code for the example adds 50 items to the ListBox using the Add method of the ListBox.ObjectCollection class and then selects three items from the list using the SetSelected method. Le code affiche ensuite des valeurs à partir de la collection ListBox.SelectedObjectCollection (via la propriété SelectedItems) et le ListBox.SelectedIndexCollection (via la propriété SelectedIndices).The code then displays values from the ListBox.SelectedObjectCollection collection (through the SelectedItems property) and the ListBox.SelectedIndexCollection (through the SelectedIndices property). Cet exemple requiert que le code se trouve dans et appelé à partir d’un Form.This example requires that the code is located in and called from a Form.

void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   
   // Create an instance of the ListBox.
   ListBox^ listBox1 = gcnew ListBox;
   
   // Set the size and location of the ListBox.
   listBox1->Size = System::Drawing::Size( 200, 100 );
   listBox1->Location = System::Drawing::Point( 10, 10 );
   
   // Add the ListBox to the form.
   this->Controls->Add( listBox1 );
   
   // Set the ListBox to display items in multiple columns.
   listBox1->MultiColumn = true;
   
   // Set the selection mode to multiple and extended.
   listBox1->SelectionMode = SelectionMode::MultiExtended;
   
   // Shutdown the painting of the ListBox as items are added.
   listBox1->BeginUpdate();
   
   // Loop through and add 50 items to the ListBox.
   for ( int x = 1; x <= 50; x++ )
   {
      listBox1->Items->Add( String::Format( "Item {0}", x ) );

   }
   listBox1->EndUpdate();
   
   // Select three items from the ListBox.
   listBox1->SetSelected( 1, true );
   listBox1->SetSelected( 3, true );
   listBox1->SetSelected( 5, true );
   
   #if defined(DEBUG)
   // Display the second selected item in the ListBox to the console.
   System::Diagnostics::Debug::WriteLine( listBox1->SelectedItems[ 1 ] );
   
   // Display the index of the first selected item in the ListBox.
   System::Diagnostics::Debug::WriteLine( listBox1->SelectedIndices[ 0 ] );
   #endif
}

private void button1_Click(object sender, System.EventArgs e)
{
   // Create an instance of the ListBox.
   ListBox listBox1 = new ListBox();
   // Set the size and location of the ListBox.
   listBox1.Size = new System.Drawing.Size(200, 100);
   listBox1.Location = new System.Drawing.Point(10,10);
   // Add the ListBox to the form.
   this.Controls.Add(listBox1);
   // Set the ListBox to display items in multiple columns.
   listBox1.MultiColumn = true;
   // Set the selection mode to multiple and extended.
   listBox1.SelectionMode = SelectionMode.MultiExtended;
 
   // Shutdown the painting of the ListBox as items are added.
   listBox1.BeginUpdate();
   // Loop through and add 50 items to the ListBox.
   for (int x = 1; x <= 50; x++)
   {
      listBox1.Items.Add("Item " + x.ToString());
   }
   // Allow the ListBox to repaint and display the new items.
   listBox1.EndUpdate();
      
   // Select three items from the ListBox.
   listBox1.SetSelected(1, true);
   listBox1.SetSelected(3, true);
   listBox1.SetSelected(5, true);

   // Display the second selected item in the ListBox to the console.
   System.Diagnostics.Debug.WriteLine(listBox1.SelectedItems[1].ToString());
   // Display the index of the first selected item in the ListBox.
   System.Diagnostics.Debug.WriteLine(listBox1.SelectedIndices[0].ToString());             
}

Private Sub button1_Click(sender As Object, e As System.EventArgs)
    ' Create an instance of the ListBox.
    Dim listBox1 As New ListBox()
    ' Set the size and location of the ListBox.
    listBox1.Size = New System.Drawing.Size(200, 100)
    listBox1.Location = New System.Drawing.Point(10, 10)
    ' Add the ListBox to the form.
    Me.Controls.Add(listBox1)
    ' Set the ListBox to display items in multiple columns.
    listBox1.MultiColumn = True
    ' Set the selection mode to multiple and extended.
    listBox1.SelectionMode = SelectionMode.MultiExtended
    
    ' Shutdown the painting of the ListBox as items are added.
    listBox1.BeginUpdate()
    ' Loop through and add 50 items to the ListBox.
    Dim x As Integer
    For x = 1 To 50
        listBox1.Items.Add("Item " & x.ToString())
    Next x
    ' Allow the ListBox to repaint and display the new items.
    listBox1.EndUpdate()
    
    ' Select three items from the ListBox.
    listBox1.SetSelected(1, True)
    listBox1.SetSelected(3, True)
    listBox1.SetSelected(5, True)
       
    ' Display the second selected item in the ListBox to the console.
    System.Diagnostics.Debug.WriteLine(listBox1.SelectedItems(1).ToString())
    ' Display the index of the first selected item in the ListBox.
    System.Diagnostics.Debug.WriteLine(listBox1.SelectedIndices(0).ToString())
End Sub

Remarques

Vous pouvez utiliser cette propriété pour définir la sélection des éléments dans un ListBoxà sélection multiple.You can use this property to set the selection of items in a multiple-selection ListBox. Pour sélectionner un élément dans un ListBoxà sélection unique, utilisez la propriété SelectedIndex.To select an item in a single-selection ListBox, use the SelectedIndex property.

S’applique à

Voir aussi