Application_Error and Global.asax.cs

In previous non Umbraco .Net solutions we implemented custom error handling in the Global.asax code behind files Application_Error event and are trying to do something similar for our new Umbraco 7 project.  Could someone direct me how to do this in Umbraco 7 as none of my attempts have worked.  I tried adding a new code behind but the code was never hit.


This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/53344-application_error-and-globalasaxcs