Automation.RemoveAutomationEventHandler 方法

定義

命名空間:

System.Windows.Automation

組件:

UIAutomationClient.dll

移除指定的消費者介面自動化事件處理常式。

public:
 static void RemoveAutomationEventHandler(System::Windows::Automation::AutomationEvent ^ eventId, System::Windows::Automation::AutomationElement ^ element, System::Windows::Automation::AutomationEventHandler ^ eventHandler);

public static void RemoveAutomationEventHandler (System.Windows.Automation.AutomationEvent eventId, System.Windows.Automation.AutomationElement element, System.Windows.Automation.AutomationEventHandler eventHandler);

static member RemoveAutomationEventHandler : System.Windows.Automation.AutomationEvent * System.Windows.Automation.AutomationElement * System.Windows.Automation.AutomationEventHandler -> unit

Public Shared Sub RemoveAutomationEventHandler (eventId As AutomationEvent, element As AutomationElement, eventHandler As AutomationEventHandler)

參數

eventId

AutomationEvent

事件識別項。

element

AutomationElement

要移除事件處理常式的消費者介面自動化專案。

eventHandler

AutomationEventHandler

針對指定的事件識別碼和消費者介面自動化專案傳遞至 AddAutomationEventHandler(AutomationEvent, AutomationElement, TreeScope, AutomationEventHandler) 的處理常式方法。

範例

下列範例程式碼顯示要新增和移除的事件處理常式。

// Member variables.
AutomationElement ElementSubscribeButton;
AutomationEventHandler UIAeventHandler;

/// <summary>
/// Register an event handler for InvokedEvent on the specified element.
/// </summary>
/// <param name="elementButton">The automation element.</param>
public void SubscribeToInvoke(AutomationElement elementButton)
{
    if (elementButton != null)
    {
        Automation.AddAutomationEventHandler(InvokePattern.InvokedEvent,
             elementButton, TreeScope.Element,
             UIAeventHandler = new AutomationEventHandler(OnUIAutomationEvent));
        ElementSubscribeButton = elementButton;
    }
}

/// <summary>
/// AutomationEventHandler delegate.
/// </summary>
/// <param name="src">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
private void OnUIAutomationEvent(object src, AutomationEventArgs e)
{
    // Make sure the element still exists. Elements such as tooltips
    // can disappear before the event is processed.
    AutomationElement sourceElement;
    try
    {
        sourceElement = src as AutomationElement;
    }
    catch (ElementNotAvailableException)
    {
        return;
    }
    if (e.EventId == InvokePattern.InvokedEvent)
    {
        // TODO Add handling code.
    }
    else
    {
        // TODO Handle any other events that have been subscribed to.
    }
}

private void ShutdownUIA()
{
    if (UIAeventHandler != null)
    {
        Automation.RemoveAutomationEventHandler(InvokePattern.InvokedEvent,
            ElementSubscribeButton, UIAeventHandler);
    }
}

' Member variables.
Private ElementSubscribeButton As AutomationElement
Private UIAeventHandler As AutomationEventHandler


''' <summary>
''' Register an event handler for InvokedEvent on the specified element.
''' </summary>
''' <param name="elementButton">The automation element.</param>
Public Sub SubscribeToInvoke(ByVal elementButton As AutomationElement)
    If (elementButton IsNot Nothing) Then
        UIAeventHandler = New AutomationEventHandler(AddressOf OnUIAutomationEvent)
        Automation.AddAutomationEventHandler(InvokePattern.InvokedEvent, elementButton, _
        TreeScope.Element, UIAeventHandler)
        ElementSubscribeButton = elementButton
    End If

End Sub


''' <summary>
''' AutomationEventHandler delegate.
''' </summary>
''' <param name="src">Object that raised the event.</param>
''' <param name="e">Event arguments.</param>
Private Sub OnUIAutomationEvent(ByVal src As Object, ByVal e As AutomationEventArgs)
    ' Make sure the element still exists. Elements such as tooltips can disappear
    ' before the event is processed.
    Dim sourceElement As AutomationElement
    Try
        sourceElement = DirectCast(src, AutomationElement)
    Catch ex As ElementNotAvailableException
        Exit Sub
    End Try
    If e.EventId Is InvokePattern.InvokedEvent Then
        ' TODO Add handling code.
    Else
    End If
    ' TODO Handle any other events that have been subscribed to.
    Console.WriteLine("Event: " & e.EventId.ProgrammaticName)
End Sub

Private Sub ShutdownUIA()
    If (UIAeventHandler IsNot Nothing) Then
        Automation.RemoveAutomationEventHandler(InvokePattern.InvokedEvent, ElementSubscribeButton, UIAeventHandler)
    End If

End Sub

另請參閱

• RemoveAllEventHandlers()
• 訂閱 UI 自動化事件
• UI 自動化事件概觀