Control.OnControlRemoved(ControlEventArgs) Méthode

Définition

Déclenche l’événement ControlRemoved.

protected:
 virtual void OnControlRemoved(System::Windows::Forms::ControlEventArgs ^ e);
protected virtual void OnControlRemoved (System.Windows.Forms.ControlEventArgs e);
abstract member OnControlRemoved : System.Windows.Forms.ControlEventArgs -> unit
override this.OnControlRemoved : System.Windows.Forms.ControlEventArgs -> unit
Protected Overridable Sub OnControlRemoved (e As ControlEventArgs)

Paramètres

e
ControlEventArgs

ControlEventArgs qui contient les données d’événement.

Exemples

L’exemple de code suivant utilise ControlRemoved pour supprimer un contrôle d’un formulaire et affiche le nom du contrôle supprimé dans un MessageBox.

   // This example demonstrates the use of the ControlAdded and
   // ControlRemoved events. This example assumes that two Button controls
   // are added to the form and connected to the addControl_Click and
   // removeControl_Click event-handler methods.
private:
   void Form1_Load( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Connect the ControlRemoved and ControlAdded event handlers
      // to the event-handler methods.
      // ControlRemoved and ControlAdded are not available at design time.
      this->ControlRemoved += gcnew System::Windows::Forms::ControlEventHandler( this, &Form1::Control_Removed );
      this->ControlAdded += gcnew System::Windows::Forms::ControlEventHandler( this, &Form1::Control_Added );
   }

   void Control_Added( Object^ /*sender*/, System::Windows::Forms::ControlEventArgs^ e )
   {
      MessageBox::Show( String::Format( "The control named {0} has been added to the form.", e->Control->Name ) );
   }

   void Control_Removed( Object^ /*sender*/, System::Windows::Forms::ControlEventArgs^ e )
   {
      MessageBox::Show( String::Format( "The control named {0} has been removed from the form.", e->Control->Name ) );
   }

   // Click event handler for a Button control. Adds a TextBox to the form.
   void addControl_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Create a new TextBox control and add it to the form.
      TextBox^ textBox1 = gcnew TextBox;
      textBox1->Size = System::Drawing::Size( 100, 10 );
      textBox1->Location = Point(10,10);

      // Name the control in order to remove it later. The name must be specified
      // if a control is added at run time.
      textBox1->Name = "textBox1";

      // Add the control to the form's control collection.
      this->Controls->Add( textBox1 );
   }

   // Click event handler for a Button control.
   // Removes the previously added TextBox from the form.
   void removeControl_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Loop through all controls in the form's control collection.
      IEnumerator^ myEnum = this->Controls->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         Control^ tempCtrl = safe_cast<Control^>(myEnum->Current);
         
         // Determine whether the control is textBox1,
         // and if it is, remove it.
         if ( tempCtrl->Name->Equals( "textBox1" ) )
         {
            this->Controls->Remove( tempCtrl );
         }
      }
   }
// This example demonstrates the use of the ControlAdded and
// ControlRemoved events. This example assumes that two Button controls
// are added to the form and connected to the addControl_Click and
// removeControl_Click event-handler methods.
private void Form1_Load(object sender, System.EventArgs e)
{
    // Connect the ControlRemoved and ControlAdded event handlers
    // to the event-handler methods.
    // ControlRemoved and ControlAdded are not available at design time.
    this.ControlRemoved += new System.Windows.Forms.ControlEventHandler(this.Control_Removed);
    this.ControlAdded += new System.Windows.Forms.ControlEventHandler(this.Control_Added);
}

private void Control_Added(object sender, System.Windows.Forms.ControlEventArgs e)
{
    MessageBox.Show("The control named " + e.Control.Name + " has been added to the form.");
}

private void Control_Removed(object sender, System.Windows.Forms.ControlEventArgs e)
{
    MessageBox.Show("The control named " + e.Control.Name + " has been removed from the form.");
}

// Click event handler for a Button control. Adds a TextBox to the form.
private void addControl_Click(object sender, System.EventArgs e)
{
    // Create a new TextBox control and add it to the form.
    TextBox textBox1 = new TextBox();
    textBox1.Size = new Size(100,10);
    textBox1.Location = new Point(10,10);
    // Name the control in order to remove it later. The name must be specified
    // if a control is added at run time.
    textBox1.Name = "textBox1";

    // Add the control to the form's control collection.
    this.Controls.Add(textBox1);
}

// Click event handler for a Button control.
// Removes the previously added TextBox from the form.
private void removeControl_Click(object sender, System.EventArgs e)
{
    // Loop through all controls in the form's control collection.
    foreach (Control tempCtrl in this.Controls)
    {
        // Determine whether the control is textBox1,
        // and if it is, remove it.
        if (tempCtrl.Name == "textBox1")
        {
            this.Controls.Remove(tempCtrl);
        }
    }
}
' This example demonstrates the use of the ControlAdded and
' ControlRemoved events. This example assumes that two Button controls 
' are added to the form and connected to the addControl_Click and 
' removeControl_Click event-handler methods.
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
    ' Connect the ControlRemoved and ControlAdded event handlers to the event-handler methods.
    ' ControlRemoved and ControlAdded are not available at design time.
    AddHandler Me.ControlRemoved, AddressOf Me.Control_Removed
    AddHandler Me.ControlAdded, AddressOf Me.Control_Added
End Sub


Private Sub Control_Added(ByVal sender As Object, ByVal e As System.Windows.Forms.ControlEventArgs)
    MessageBox.Show(("The control named " + e.Control.Name + " has been added to the form."))
End Sub


Private Sub Control_Removed(ByVal sender As Object, ByVal e As System.Windows.Forms.ControlEventArgs)
    MessageBox.Show(("The control named " + e.Control.Name + " has been removed from the form."))
End Sub


' Click event handler for a Button control. Adds a TextBox to the form.
Private Sub addControl_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
    ' Create a new TextBox control and add it to the form.
    Dim textBox1 As New TextBox()
    textBox1.Size = New Size(100, 10)
    textBox1.Location = New Point(10, 10)
    ' Name the control in order to remove it later. 
    ' The name must be specified if a control is added at run time.
    textBox1.Name = "textBox1"

    ' Add the control to the form's control collection.
    Me.Controls.Add(textBox1)
End Sub


' Click event handler for a Button control.
' Removes the previously added TextBox from the form.
Private Sub removeControl_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button2.Click
    ' Loop through all controls in the form's control collection.
    Dim tempCtrl As Control
    For Each tempCtrl In Me.Controls
        ' Determine whether the control is textBox1,
        ' and if it is, remove it.
        If tempCtrl.Name = "textBox1" Then
            Me.Controls.Remove(tempCtrl)
        End If
    Next tempCtrl
End Sub

Remarques

Appelé lorsqu’un contrôle enfant est supprimé du contrôle.

Le déclenchement d'un événement appelle le gestionnaire des événements par l'intermédiaire d'un délégué. Pour plus d’informations, consultez gestion et déclenchement d’événements.

La méthode OnControlRemoved permet également aux classes dérivées de gérer l'événement sans y attacher de délégué. Il s'agit de la méthode recommandée pour gérer l'événement dans une classe dérivée.

Notes pour les héritiers

Lors de la substitution de OnControlRemoved(ControlEventArgs) dans une classe dérivée, veillez à appeler la méthode OnControlRemoved(ControlEventArgs) de la classe de base de manière à ce que les délégués inscrits reçoivent l'événement.

S’applique à

Voir aussi