Can you lock on a generic dictionary?

Question

Or should you always create some other lock object?

Answer 1

Yes, cast it to an IDictionary and lock on .SyncRoot:

Generic.Dictionary<int, int> dic = new Generic.Dictionary<int, int>();

lock (((IDictionary)dic).SyncRoot)
{
    // code
}

Thanks to this source for the info.

Of course a thread-safe dictionary would be nice, too, as others have suggested.

Answer 2

You can lock on any object that you wish (except value-types). It's recommended though to lock on the .SyncRoot object.