AccessViolationException: 尝试读取或写入受保护的内存。这通常指示其他内存已损坏。
StackTrace:
   在 System.Windows.Forms.UnsafeNativeMethods.DispatchMessageA(MSG& msg)
   在 System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
   在 System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
   在 System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
   在 System.Windows.Forms.Form.ShowDialog(IWin32Window owner)
   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)