I’m sure I’m not the first person to come up with this.  However, I haven’t noticed anyone publish a trick like this since I started paying close attention to the community last July.  So, I thought I’d post it this quick and easy debug tip.

I’m working on an event receiver that started to generate this error in the 12 hive:

Error loading and running event receiver Conchango.xyzzyEventReceiver in xyzzy, Version=1.0.0.0, Culture=neutral, PublicKeyToken=blahbalhbalh. Additional information is below.  : Object reference not set to an instance of an object.    

I didn’t know where I had introduced this bug because I had done too many things in one of my code/deploy/test cycles. 

I tried this solution to get my pdb in there with hopes that SharePoint’s 12 hive would show the stack trace, but no luck.  I don’t know if it’s possible and if someone does, please let me know 🙂

I know it’s possible to write your own log messages to the 12 hive.  Frankly, I wanted something a little less scary and quicker to implement.

It occurred to me that I could at least get some basic trace information by catching and re-throwing generic exceptions like this:

  try {
    UpdateEditionDate(properties);
  }
  catch (Exception e)
  {
    throw new Exception("Dispatcher, UpdateEditionDate(): Exception: [" + e.ToString() + "].");
  }

This showed up in the 12 hive thusly:

Error loading and running event receiver Conchango.xyzzyEventReceiver in xyzzy, Version=1.0.0.0, Culture=neutral, PublicKeyToken=blahblahblah. Additional information is below.  : Dispatcher, UpdateEditionDate(): Exception: [System.NullReferenceException: Object reference not set to an instance of an object.     at Conchango.xyzzyManagementEventReceiver.UpdateEditionDate(SPItemEventProperties properties)     at Conchango.xyzzyManagementEventReceiver.Dispatcher(SPItemEventProperties properties, String eventDescription)].

That gave me all the detail I needed to track down that particular problem and I expect to use it a lot going forward.

</end>

Subscribe to my blog!