How to remove from one list all the items in another?

Question

I\'m reading a set of rows from a remote database, and a similar set from a local database, and then using RemoveAll to get rid of remote rows that are already present locally..

Answer 1

I'm trying to do this without visual studio, so I'm not sure if this will work, but I'd suppose you could do something along these lines if what you're trying to do is compare the Identifier:

    Remote_Events = (From r_evt In Remote_Events
                    Where Not ((From l_evt In Local_Events Select l_evt.Identifier).Contains(r_evt.Identifier))
                    Select r_evt).ToList

I hope this helps and at least moves you in the right direction.

Answer 2

One way is this:

    remote_events.RemoveAll(Function(e) local_events.Exists(Function(f) f.Identifier = e.Identifier))