IDropTarget.OnDragEnter(DragEventArgs) IDropTarget.OnDragEnter(DragEventArgs) IDropTarget.OnDragEnter(DragEventArgs) IDropTarget.OnDragEnter(DragEventArgs) Method

定義

引發 DragEnter 事件。Raises the DragEnter event.

public:
 void OnDragEnter(System::Windows::Forms::DragEventArgs ^ e);
public void OnDragEnter (System.Windows.Forms.DragEventArgs e);
abstract member OnDragEnter : System.Windows.Forms.DragEventArgs -> unit
Public Sub OnDragEnter (e As DragEventArgs)

參數

e
DragEventArgs DragEventArgs DragEventArgs DragEventArgs

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

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.

OnDragEnter 方法也允許衍生類別處理事件,而不用附加委派。The 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.

給實施者的注意事項

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

適用於