Windows 窗体崩溃：在全局异常处理程序中捕获到意外的 NullReferenceException

Question

We have developed a windows forms application that captures user interactions ie Typed text, clicks. Sometimes, out of the blue on some machine, we get the following exception:

Object reference not set to an instance of an object.

   at System.Environment.GetStackTrace(Exception e, Boolean needFileInfo)
   at System.Environment.get_StackTrace()
   at Recorder.Program.GlobalExceptionHandler(Object sender, UnhandledExceptionEventArgs args)
   at System.Windows.Forms.UnsafeNativeMethods.PeekMessage(MSG& msg, HandleRef hwnd, Int32 msgMin, Int32 msgMax, Int32 remove)
   at System.Windows.Forms.UnsafeNativeMethods.PeekMessage(MSG& msg, HandleRef hwnd, Int32 msgMin, Int32 msgMax, Int32 remove)
   at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
   at Recorder.Program.Main(String[] args)

The issue is not replicated in Development or Testing environment, but occurs in release. Though all our code is covered with exception handling, the above error occurs in the main method and gets caught in the GlobalExcptionHandler. The exception has no details nor stack trace.

ExceptionMessage - Object reference not set to an instance of an object. 
ExceptionSource -   
ExceptionTarget -   
StackTrace - Logging Stack Trace is disabled

I tried to look up the issue online, found the following links those seems similar, but again with no solutions :

http://arnosoftwaredev.blogspot.com/2005/07/pragmatic-solutions-for-imperfect.html

http://dotnet.community/threads/somebody-help-me-with-this-error-plz.13965/#post-60920

Usually we have noticed, it gets crashed soon after installing the product, or when resource-intensive applications are running ie MS Teams, MS Excel

Please guide!

Answer 1

I would start by looking at any info or warning messages in the compiler "Error list" tab. The Roslyn compiler is generally pretty good at pointing out uninitialised variables. Once you have fixed all those warnings/info, turn on "Warnings as errors" to make sure you don't get any new ones.

Also, look for any conditionally compiled code:

#if DEBUG
.. something gets initialised  
#endif