Control Methods


.NET Framework Class Library
Control..::.OnClick Method

Raises the Click event.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)
Syntax

Visual Basic (Declaration)
Protected Overridable Sub OnClick ( _
    e As EventArgs _
)
Visual Basic (Usage)
Dim e As EventArgs

Me.OnClick(e)
C#
protected virtual void OnClick(
    EventArgs e
)
Visual C++
protected:
virtual void OnClick(
    EventArgs^ e
)
JScript
protected function OnClick(
    e : EventArgs
)

Parameters

e
Type: System..::.EventArgs
An EventArgs that contains the event data.
Remarks

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnClick method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors:

When overriding OnClick in a derived class, be sure to call the base class's OnClick method so that registered delegates receive the event.

Examples

The following code example demonstrates overriding the OnClick method in a derived class. To run the example, paste the following code after a form class, in the same file. Add a textbox of type SingleClickTextBox to the form.

Visual Basic
' 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
C#
// 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);
    }


}
Visual C++
// 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 );
   }
};

The following code example shows one of the many uses of the Click event and event handler.

Visual Basic
' 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
C#
// 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;
}
Visual C++
   // 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;
   }
Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0
See Also

Reference

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