protected virtual void Dispose(bool disposing)
 {
     if (!_disposed)
     {
         if (disposing)
         {
             canvas.Dispose();
             canvas = null;
             WebPart.Dispose();
             WebPart = null;
         }
         _disposed = true;
     }
 }
 public void InstantiateIn(Control container)
 {
     canvas         = new FormCanvas(InnerHTML, container);
     canvas.WebPart = WebPart as FormWebPart;
     container.Controls.Add(canvas);
 }