/// <summary>
/// DesignRectangle控件鼠标左键按下
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void dr_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
DesignRectangle item = sender as DesignRectangle;
mouseVerticalPosition = e.GetPosition(cvsPanle).Y;
mouseHorizontalPosition = e.GetPosition(cvsPanle).X;
isMouseCaptured = true;
isMoveByDesignRectangle = false;
item.CaptureMouse();
e.Handled = true;
line_Top.Visibility = System.Windows.Visibility.Visible;
line_Left.Visibility = System.Windows.Visibility.Visible;
}