Control.OnClick(EventArgs) Control.OnClick(EventArgs) Control.OnClick(EventArgs) Control.OnClick(EventArgs) Method

Definition

Löst das Click-Ereignis aus.Raises the Click event.

protected:
 virtual void OnClick(EventArgs ^ e);
protected virtual void OnClick (EventArgs e);
abstract member OnClick : EventArgs -> unit
override this.OnClick : EventArgs -> unit
Protected Overridable Sub OnClick (e As EventArgs)

Parameter

e
EventArgs EventArgs EventArgs EventArgs

Ein EventArgs, das die Ereignisdaten enthält.An EventArgs that contains the event data.

Beispiele

Im folgenden Codebeispiel wird das über OnClick Schreiben der-Methode in einer abgeleiteten Klasse veranschaulicht.The following code example demonstrates overriding the OnClick method in a derived class. Fügen Sie den folgenden Code nach einer Formular Klasse in dieselbe Datei ein, um das Beispiel auszuführen.To run the example, paste the following code after a form class, in the same file. Fügen Sie dem Formular ein Textfeld vom Typ SingleClickTextBox hinzu.Add a textbox of type SingleClickTextBox to the form.

// This is a custom TextBox control that overrides the OnClick method
// to allow one-click selection of the text in the text box.
public ref class SingleClickTextBox: public TextBox
{
protected:
   virtual void OnClick( EventArgs^ e ) override
   {
      this->SelectAll();
      TextBox::OnClick( e );
   }
};
// This is a custom TextBox control that overrides the OnClick method
// to allow one-click selection of the text in the text box.

public class SingleClickTextBox: TextBox

{
	protected override void OnClick(EventArgs e)
	{
		this.SelectAll();
		base.OnClick(e);
	}


}
' This is a custom TextBox control that overrides the OnClick method
' to allow one-click selection of the text in the text box.

Public Class SingleClickTextBox
    Inherits TextBox

    Protected Overrides Sub OnClick(ByVal e As EventArgs)
        Me.SelectAll()
        MyBase.OnClick(e)
    End Sub


End Class

Das folgende Codebeispiel zeigt eine der vielen Verwendungsmöglichkeiten des- Click Ereignisses und des-Ereignis Handlers.The following code example shows one of the many uses of the Click event and event handler.

   // This example uses the Parent property and the Find method of Control to set
   // properties on the parent control of a Button and its Form. The example assumes
   // that a Button control named button1 is located within a GroupBox control. The 
   // example also assumes that the Click event of the Button control is connected to
   // the event handler method defined in the example.
private:
   void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Get the control the Button control is located in. In this case a GroupBox.
      Control^ control = button1->Parent;
      
      // Set the text and backcolor of the parent control.
      control->Text = "My Groupbox";
      control->BackColor = Color::Blue;
      
      // Get the form that the Button control is contained within.
      Form^ myForm = button1->FindForm();
      
      // Set the text and color of the form containing the Button.
      myForm->Text = "The Form of My Control";
      myForm->BackColor = Color::Red;
   }
// This example uses the Parent property and the Find method of Control to set
// properties on the parent control of a Button and its Form. The example assumes
// that a Button control named button1 is located within a GroupBox control. The 
// example also assumes that the Click event of the Button control is connected to
// the event handler method defined in the example.
private void button1_Click(object sender, System.EventArgs e)
{
   // Get the control the Button control is located in. In this case a GroupBox.
   Control control = button1.Parent;
   // Set the text and backcolor of the parent control.
   control.Text = "My Groupbox";
   control.BackColor = Color.Blue;
   // Get the form that the Button control is contained within.
   Form myForm = button1.FindForm();
   // Set the text and color of the form containing the Button.
   myForm.Text = "The Form of My Control";
   myForm.BackColor = Color.Red;
}
' This example uses the Parent property and the Find method of Control to set
' properties on the parent control of a Button and its Form. The example assumes
' that a Button control named button1 is located within a GroupBox control. The 
' example also assumes that the Click event of the Button control is connected to
' the event handler method defined in the example.
Private Sub button1_Click(sender As Object, e As System.EventArgs) Handles button1.Click
   ' Get the control the Button control is located in. In this case a GroupBox.
   Dim control As Control = button1.Parent
   ' Set the text and backcolor of the parent control.
   control.Text = "My Groupbox"
   control.BackColor = Color.Blue
   ' Get the form that the Button control is contained within.
   Dim myForm As Form = button1.FindForm()
   ' Set the text and color of the form containing the Button.
   myForm.Text = "The Form of My Control"
   myForm.BackColor = Color.Red
End Sub

Hinweise

Durch das Auslösen eines Ereignisses wird der Ereignishandler über einen Delegaten aufgerufen.Raising an event invokes the event handler through a delegate. Weitere Informationen finden Sie unter Behandeln und Auslösen von Ereignissen.For more information, see Handling and Raising Events.

Mit der OnClick-Methode können auch abgeleitete Klassen das Ereignis ohne Anfügen eines Delegaten behandeln.The OnClick method also allows derived classes to handle the event without attaching a delegate. Dies ist das bevorzugte Verfahren für die Behandlung des Ereignisses in einer abgeleiteten Klasse.This is the preferred technique for handling the event in a derived class.

Hinweise für Vererber

Wenn Sie OnClick(EventArgs) in einer abgeleiteten Klasse überschreiben, müssen Sie die OnClick(EventArgs)-Methode der Basisklasse aufrufen, damit registrierte Delegaten das Ereignis empfangen.When overriding OnClick(EventArgs) in a derived class, be sure to call the base class's OnClick(EventArgs) method so that registered delegates receive the event.

Gilt für:

Siehe auch