QueryContinueDragEventArgs.Action QueryContinueDragEventArgs.Action QueryContinueDragEventArgs.Action QueryContinueDragEventArgs.Action Property

定义

获取或设置拖放操作的状态。Gets or sets the status of a drag-and-drop operation.

public:
 property System::Windows::Forms::DragAction Action { System::Windows::Forms::DragAction get(); void set(System::Windows::Forms::DragAction value); };
public System.Windows.Forms.DragAction Action { get; set; }
member this.Action : System.Windows.Forms.DragAction with get, set
Public Property Action As DragAction

属性值

示例

此代码摘录演示了如何QueryContinueDragEventArgs将类QueryContinueDrag与事件一起使用。This code excerpt demonstrates using the QueryContinueDragEventArgs class with the QueryContinueDrag event. 有关完整的代码示例, 请参阅方法。DoDragDropSee the DoDragDrop method for the complete code example.

void ListDragSource_QueryContinueDrag( Object^ sender, System::Windows::Forms::QueryContinueDragEventArgs^ e )
{
   // Cancel the drag if the mouse moves off the form.
   ListBox^ lb = dynamic_cast<ListBox^>(sender);
   if ( lb != nullptr )
   {
      Form^ f = lb->FindForm();

      // Cancel the drag if the mouse moves off the form. The screenOffset
      // takes into account any desktop bands that may be at the top or left
      // side of the screen.
      if ( ((Control::MousePosition.X - screenOffset.X) < f->DesktopBounds.Left) || ((Control::MousePosition.X - screenOffset.X) > f->DesktopBounds.Right) || ((Control::MousePosition.Y - screenOffset.Y) < f->DesktopBounds.Top) || ((Control::MousePosition.Y - screenOffset.Y) > f->DesktopBounds.Bottom) )
      {
         e->Action = DragAction::Cancel;
      }
   }
}
private void ListDragSource_QueryContinueDrag(object sender, System.Windows.Forms.QueryContinueDragEventArgs e) {
    // Cancel the drag if the mouse moves off the form.
    ListBox lb = sender as ListBox;

    if (lb != null) {

        Form f = lb.FindForm();

        // Cancel the drag if the mouse moves off the form. The screenOffset
        // takes into account any desktop bands that may be at the top or left
        // side of the screen.
        if (((Control.MousePosition.X - screenOffset.X) < f.DesktopBounds.Left) ||
            ((Control.MousePosition.X - screenOffset.X) > f.DesktopBounds.Right) ||
            ((Control.MousePosition.Y - screenOffset.Y) < f.DesktopBounds.Top) ||
            ((Control.MousePosition.Y - screenOffset.Y) > f.DesktopBounds.Bottom)) {

            e.Action = DragAction.Cancel;
        }
    }
}
Private Sub ListDragSource_QueryContinueDrag(ByVal sender As Object, ByVal e As QueryContinueDragEventArgs) Handles ListDragSource.QueryContinueDrag
    ' Cancel the drag if the mouse moves off the form.
    Dim lb as ListBox = CType(sender, System.Windows.Forms.ListBox)

    If (lb isNot nothing) Then

        Dim f as Form = lb.FindForm()

        ' Cancel the drag if the mouse moves off the form. The screenOffset
        ' takes into account any desktop bands that may be at the top or left
        ' side of the screen.
        If (((Control.MousePosition.X - screenOffset.X) < f.DesktopBounds.Left) Or _
            ((Control.MousePosition.X - screenOffset.X) > f.DesktopBounds.Right) Or _
            ((Control.MousePosition.Y - screenOffset.Y) < f.DesktopBounds.Top) Or _
            ((Control.MousePosition.Y - screenOffset.Y) > f.DesktopBounds.Bottom)) Then

            e.Action = DragAction.Cancel
        End If
    End if
End Sub

注解

默认情况下,如果按 Esc 键,则 QueryContinueDrag 事件将 Action 设置为 DragAction.Cancel;如果按鼠标左键、中键或右键,则将 Action 设置为 DragAction.DropBy default, the QueryContinueDrag event sets Action to DragAction.Cancel if the ESC key was pressed and sets Action to DragAction.Drop if the left, middle, or right mouse button is pressed.

适用于

另请参阅