Raise Events from a UI Automation Provider

Note

This documentation is intended for .NET Framework developers who want to use the managed UI Automation classes defined in the System.Windows.Automation namespace. For the latest information about UI Automation, see Windows Automation API: UI Automation.

This topic contains example code that shows how to raise an event from a UI Automation provider.

Example

In the following example, a UI Automation event is raised in the implementation of a custom button control. The implementation enables a UI Automation client application to simulate a button click.

To avoid unnecessary processing, the example checks ClientsAreListening to see whether events should be raised.

''' <summary>
''' Responds to a button click, regardless of whether it was caused by a 
''' mouse or keyboard click or by InvokePattern.Invoke. 
''' </summary>
Private Sub OnCustomButtonClicked()

    '' TODO  Perform program actions invoked by the control.

    '' Raise an event.
    If AutomationInteropProvider.ClientsAreListening Then
        Dim args As AutomationEventArgs = _
            New AutomationEventArgs(InvokePatternIdentifiers.InvokedEvent)
        AutomationInteropProvider.RaiseAutomationEvent( _
            InvokePatternIdentifiers.InvokedEvent, Me, args)
    End If
End Sub
/// <summary>
/// Responds to a button click, regardless of whether it was caused by a mouse or
/// keyboard click or by InvokePattern.Invoke. 
/// </summary>
private void OnCustomButtonClicked()
{
    // TODO  Perform program actions invoked by the control.

    // Raise an event.
    if (AutomationInteropProvider.ClientsAreListening)
    {
        AutomationEventArgs args = new AutomationEventArgs(InvokePatternIdentifiers.InvokedEvent);
        AutomationInteropProvider.RaiseAutomationEvent(InvokePatternIdentifiers.InvokedEvent, this, args);
    }
}

See Also

Concepts

UI Automation Providers Overview