Can multiple threads modify a dictionary?

Question

In C#, can multiple threads read and write to a Dictionary provided each thread only accesses one element in the dictionary and never accesses another?

Answer 1

No, a Dictionary is not Thread-safe.

With the exception of modifying the contents of a reference type (object) that is stored as the Value in a dictionary.

In .NET 4 we will have System.Collections.Concurrent.ConcurrentDictionary.