UIElement.PreviewTouchDown UIElement.PreviewTouchDown UIElement.PreviewTouchDown UIElement.PreviewTouchDown Event


手指在這個項目上方且在螢幕上觸控時發生。Occurs when a finger touches the screen while the finger is over this element.

 event EventHandler<System::Windows::Input::TouchEventArgs ^> ^ PreviewTouchDown;
public event EventHandler<System.Windows.Input.TouchEventArgs> PreviewTouchDown;
member this.PreviewTouchDown : EventHandler<System.Windows.Input.TouchEventArgs> 
Public Custom Event PreviewTouchDown As EventHandler(Of TouchEventArgs) 


根據預設,PreviewTouchDownTouchDown手指觸控螢幕,並移動之前不會發生的事件。By default, the PreviewTouchDown and TouchDown events do not occur until a finger touches the screen and moves. 手指在螢幕上按住卻不必移動它會使用按下並按住行為StylusPressing a finger on the screen and holding it without moving it causes the press and hold behavior of a Stylus. 按住不放的行為相當於按一下滑鼠右鍵。The press and hold behavior is equivalent to a mouse right-click.

會造成PreviewTouchDownTouchDown事件發生在手指觸控螢幕,如設定Stylus.IsPressAndHoldEnabled; 附加屬性false此元素。To cause the PreviewTouchDown and TouchDown events to occur as soon as a finger touches the screen, set the Stylus.IsPressAndHoldEnabled attached property to false for this element.

路由事件資訊Routed Event Information

識別項欄位Identifier field PreviewTouchDownEvent
路由策略Routing strategy 通道Tunneling
Delegate - 委派Delegate 型別 EventHandler<TEventArgs>TouchEventArgsEventHandler<TEventArgs> of type TouchEventArgs.