WorkflowDesignerMessageFilter.OnKeyDown(KeyEventArgs) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
發生於按下按鍵時。
protected:
virtual bool OnKeyDown(System::Windows::Forms::KeyEventArgs ^ eventArgs);
protected virtual bool OnKeyDown (System.Windows.Forms.KeyEventArgs eventArgs);
abstract member OnKeyDown : System.Windows.Forms.KeyEventArgs -> bool
override this.OnKeyDown : System.Windows.Forms.KeyEventArgs -> bool
Protected Overridable Function OnKeyDown (eventArgs As KeyEventArgs) As Boolean
參數
- eventArgs
- KeyEventArgs
KeyEventArgs,包含事件的相關資訊。
傳回
如果要處理訊息為 true
,否則為 false
。
範例
下列程式碼範例會示範如何覆寫 OnKeyDown 方法,自訂從工作流程設計介面移除活動的方法。
這個程式碼範例是 DesignerShell.cs 檔案中<Basic Designer Hosting SDK>範例的一部分。 如需詳細資訊,請參閱 基本設計工具裝載。
protected override bool OnKeyDown(KeyEventArgs eventArgs)
{
if (eventArgs.KeyCode == Keys.Delete)
{
ISelectionService selectionService = (ISelectionService)serviceProvider.GetService(typeof(ISelectionService));
if (selectionService != null && selectionService.PrimarySelection is CodeActivity)
{
CodeActivity codeActivityComponent = (CodeActivity)selectionService.PrimarySelection;
CompositeActivity parentActivity = codeActivityComponent.Parent;
if (parentActivity != null)
{
parentActivity.Activities.Remove(codeActivityComponent);
this.ParentView.Update();
}
loader.RemoveActivityFromDesigner(codeActivityComponent);
}
}
return true;
}
Protected Overrides Function OnKeyDown(ByVal eventArgs As KeyEventArgs) As Boolean
If eventArgs.KeyCode = Keys.Delete Then
Dim selectionService As ISelectionService = CType(serviceProvider.GetService(GetType(ISelectionService)), ISelectionService)
If selectionService IsNot Nothing AndAlso TypeOf selectionService.PrimarySelection Is CodeActivity Then
Dim codeActivityComponent As CodeActivity = CType(selectionService.PrimarySelection, CodeActivity)
Dim parentActivity As CompositeActivity = codeActivityComponent.Parent
If parentActivity IsNot Nothing Then
parentActivity.Activities.Remove(codeActivityComponent)
Me.ParentView.Update()
End If
loader.RemoveActivityFromDesigner(codeActivityComponent)
End If
End If
Return True
End Function
備註
OnKeyDown 發生於當特定物件擁有焦點,且按下按鍵時。