WorkflowDesignerMessageFilter.OnKeyDown(KeyEventArgs) 方法

定義

命名空間:

System.Workflow.ComponentModel.Design

組件:

System.Workflow.ComponentModel.dll

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

Boolean

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Designer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。

另請參閱

• 基本Designer裝載