Thanks for your reply.

Hi,
You can changed the drawingdocument.Settings.MaxZoomFactor setting if you want to allow the view to zoom to a larger zoom factor. By default this value is set to 10, but you can increase it to any number.

Best Regards,
Nevron Support Team

Hi:
      When I zoom the DrawingView to 15,It appear at the wrong tip that "The specified zoom factor is not valid"?
      could I reset the maximum zoom factor to 20?
      Thank you.