Wpf鼠标点击坐标转为屏幕坐标/后台重新设置在Canvas和Grid上的位置

Point getP = PointToScreen(Mouse.GetPosition(this));

DockPanel.SetValue(Canvas.LeftProperty, 1.0);
            DockPanel.SetValue(Canvas.TopProperty , 5.0);
            DockPanel.SetValue(Grid.RowProperty, 5);
            DockPanel.SetValue(Grid.ColumnProperty, 3);