is locking necessary for Dictionary lookup?

Question

lock(dictionaryX)
{
   dictionaryX.TryGetValue(key, out value);
}

is locking necessary while doing lookups to a Dictionary ?

THe program is

Answer 1

If you are on .Net 4, you can replace with ConcurrentDictionary to do this safely. There are other similar collections, preferred when you need multithreaded access, in the System.Collection.Concurrent namespace.

Don't use roll-your-own locking if this is an option for you.