What's the best way of implementing a thread-safe Dictionary?

Question

I was able to implement a thread-safe Dictionary in C# by deriving from IDictionary and defining a private SyncRoot object:

public class SafeDictionary<TKey, TValue>: IDictionary<TKey, TValue> {     private readonly object syncRoot = new object();     private Dictionary<TKey, TValue> d = new Dictionary<TKey, TValue>();      public object SyncRoot     {         get { return syncRoot; }     }       public void Add(TKey key, TValue value)     {         lock (syncRoot)         {             d.Add(key, value);         }     }      // more IDictionary members... } 

I then lock on this SyncRoot object throughout my consumers (multiple threads):

Example:

lock (m_MySharedDictionary.SyncRoot) {     m_MySharedDictionary.Add(...); } 

I was able to make it work, but this resulted in some ugly code. My question is, is there a better, more elegant way of implementing a thread-safe Dictionary?

Answer 1

The .NET 4.0 class that supports concurrency is named ConcurrentDictionary.