Question

In C#, will the folloing code throw e containing the additional information up the call stack?

...
catch(Exception e)
{
  e.Data.Add("Additional information","blah blah");
  throw;
}

Answer 1

Yes, it will. A lot of developers don’t realise that the following code will throw a new exception from that point in the call-stack, not the calls made previously up the stack before the catch.

...
catch(Exception e)
{
  e.Data.Add("Additional information","blah blah");
  throw e;
}

I learnt this the hard way!