OnClick Method

ControlDesigner.OnClick Method (DesignerRegionMouseEventArgs)

 

Called by the design host when the user clicks the associated control at design time.

Namespace:   System.Web.UI.Design
Assembly:  System.Design (in System.Design.dll)

protected virtual void OnClick(
	DesignerRegionMouseEventArgs e
)

Parameters

e
Type: System.Web.UI.Design.DesignerRegionMouseEventArgs

A DesignerRegionMouseEventArgs object that specifies the location and, possibly, the control designer region that the user clicked.

The ViewEvent event is raised by the design host for certain actions on a control in the design surface. For example, an event is raised for the following conditions:

  • The user clicks the control.

  • The control designer paints on the design surface.

  • The user enters or exits template editing mode for the control.

The ControlDesigner class supplies a default delegate to handle the IControlDesignerView.ViewEvent event. Classes deriving from ControlDesigner override the OnClick method to process events that are raised when the user clicks a control.

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

The default implementation of the OnClick method returns without performing any processing.

Notes to Inheritors:

Override the OnClick method in a class deriving from the ControlDesigner class to handle design-time click events on the control. If e is not null, the clicked region, if any, is specified in the Region property.

The following code example shows how to use a handler for the OnClick event in a clickable region of the control and use a DesignerRegionMouseEventArgs object to identify the region that is being clicked.

This code example is part of a larger code example for the EditableDesignerRegion class.

// Handler for the Click event, which provides the region in the arguments.
protected override void OnClick(DesignerRegionMouseEventArgs e)
{
    if (e.Region == null)
        return;

    // If the clicked region is not a header, return
    if (e.Region.Name.IndexOf("Header") != 0)
        return;

    // Switch the current view if required
    if (e.Region.Name.Substring(6, 1) != myControl.CurrentView.ToString())
    {
        myControl.CurrentView = int.Parse(e.Region.Name.Substring(6, 1));
        base.UpdateDesignTimeHtml();
    }
}

.NET Framework
Available since 2.0
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