ToolStripItem.IDropTarget.OnDragEnter(DragEventArgs) 方法

定義

引發 DragEnter 事件。Raises the DragEnter event.

 virtual void System.Windows.Forms.IDropTarget.OnDragEnter(System::Windows::Forms::DragEventArgs ^ dragEvent) = System::Windows::Forms::IDropTarget::OnDragEnter;
void IDropTarget.OnDragEnter (System.Windows.Forms.DragEventArgs dragEvent);
abstract member System.Windows.Forms.IDropTarget.OnDragEnter : System.Windows.Forms.DragEventArgs -> unit
override this.System.Windows.Forms.IDropTarget.OnDragEnter : System.Windows.Forms.DragEventArgs -> unit
Sub OnDragEnter (dragEvent As DragEventArgs) Implements IDropTarget.OnDragEnter

參數

dragEvent
DragEventArgs

DragEventArgs,其中包含事件資料。A DragEventArgs that contains the event data.

實作

備註

引發事件會透過委派叫用此事件處理常式。Raising an event invokes the event handler through a delegate. 如需詳細資訊,請參閱 處理和引發事件For more information, see Handling and Raising Events.

IDropTarget.OnDragEnter 方法也允許衍生類別處理事件,而不用附加委派。The IDropTarget.OnDragEnter method also allows derived classes to handle the event without attaching a delegate. 這是在衍生類別中處理事件的慣用技巧。This is the preferred technique for handling the event in a derived class.

給繼承者的注意事項

IDropTarget.OnDragEnter(DragEventArgs)在衍生類別中覆寫時,請務必呼叫基類的方法, IDropTarget.OnDragEnter(DragEventArgs) 以便註冊的委派會接收事件。When overriding IDropTarget.OnDragEnter(DragEventArgs) in a derived class, be sure to call the base class' IDropTarget.OnDragEnter(DragEventArgs) method so that registered delegates receive the event.

適用於