WorkflowDesignerMessageFilter.OnKeyDown(KeyEventArgs) Method

Reference

Definition

Namespace:: System.Workflow.ComponentModel.Design

Assembly:: System.Workflow.ComponentModel.dll

Important

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Occurs when a key is pressed.

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

Parameters

eventArgs: KeyEventArgs

A KeyEventArgs that contains information about the event.

Returns

Boolean

true if the message is handled; otherwise, false.

Examples

The following code example shows how to override the OnKeyDown method to customize how to remove activities from a workflow design surface.

This code example is part of the Basic Designer Hosting SDK Sample from the DesignerShell.cs file. For more information, see Basic Designer Hosting.

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

Remarks

OnKeyDown occurs when a key is pressed when a specific object has focus.

Applies to