Question

What is the best way to handle an exception?
Also, why should I never write:

catch (Exception ex) { throw ex; }

Answer 1

The best way to handle an exception is to do something meaningful in the catch block (the one which in your example contains throw ex). The definition of “meaningful” completely depends on your needs.

You should not do catch (Exception ex) { throw ex; } because that brakes the exception chain. It is perfectly fine to catch an exception, handle it and re-throw so that the calling code can see it, but you should be doing so like this:

catch (Exception ex) { /* handling code; */ throw; }