AccessViolationException
   在 System.Drawing.SafeNativeMethods.Gdip.GdipMeasureString(HandleRef graphics, String textString, Int32 length, HandleRef font, GPRECTF& layoutRect, HandleRef stringFormat, GPRECTF& boundingBox, Int32& codepointsFitted, Int32& linesFilled)
   在 System.Drawing.Graphics.MeasureString(String text, Font font, SizeF layoutArea, StringFormat stringFormat)
   在 System.Drawing.Graphics.MeasureString(String text, Font font, Int32 width)
   在 System.Windows.Forms.ThreadExceptionDialog..ctor(Exception t)
   在 System.Windows.Forms.Application.ThreadContext.OnThreadException(Exception t)
   在 System.Windows.Forms.Control.WndProcException(Exception e)
   在 System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)