First, there’s the infinitely recursive call that Marc pointed out in his comment above. (Who writes this crap?)

Second, I fixed the issue that Pete found with not raising the change notification for “Item[]” when a set occurs (see pingback comment above). This was actually a regression from an earlier fix. Doh! (Seriously, doesn’t anyone unit test these things!?)

Big thanks to Pete and Marc!

thx for the great work.
With VS 2010RC1 I got a Stackoverflow in Line 445. Replacing the Line with
get { return ((IDictionary<TKey, TValue>)this)[(TKey)key]; }
helped.

Marc

Thanks for the class! Saved me a lot of time. One thing, I’m using it in VS 2010 B2 and get 3 CS0693 warnings. These look like BS warnings to me, but apperently Microsoft decided you can’t use the same names for inner template params as you do for the outer ones. The warnings are because you named all the collection params as TKey and TValue.

My implementation of the ObservableDictionary class includes all of the interfaces implemented by the native Dictionary class in the full .NET framework. Silverlight uses a compact version of the .NET framework. The CoreCLR for Silverlight defines the Dictionary class as follows:

public class Dictionary<TKey, TValue> :
    IDictionary<TKey, TValue>,
    ICollection<KeyValuePair<TKey, TValue>>,
    IEnumerable<KeyValuePair<TKey, TValue>>,
    IDictionary,
    ICollection,
    IEnumerable

Note that the serialization interfaces simply don’t exist in Silverlight’s CoreCLR. This means you can create an ObservableDictionary for Silverlight that is fully analogous to the native Dictionary class without supporting serialization.

Of course, if you actually need to serialize the dictionary (for storage, remoting, etc), then I see no problem with using the XML serialization interfaces.

Cheers,
-dw

wow since 2007 (when you wrote it) has now more than 2 years passed by and I can even now after so many years use your great class. I am trying to use your Observabledictionary under silverlight 3. MS didn’t make any improvements in this field since ver.2. I’ve noticed that the ISerializable and IDeserializable are not supported in SL. So your serialization part doesn’t work in SL.
My question is. If I replace not working Ser/DeSer code with IXmlSerializable and methods like write-/readXML would it be enough?

Thanks for your great work
Rafal

You should be able to cast the dictionary to INotifyCollectionChanged to add the handler:

(aDict as INotifyCollectionChanged).CollectionChanged += …

Cheers,
-dw

ObservableDictionary aDict = new ObservableDictionary();
aDict.CollectionChanged += OnCollectionChanged;

Thank for the great work!

Chip

There are actually lots of optimizations that could be made to this class, but I’ve not had the bandwidth to properly test such changes, and I continue to procrastinate there. I took a lot of shortcuts (like editing an item by simply removing the old and adding the new) when I first put the class together.

I’m happy to post any suggested improvements that have been tested. You can reach me at ask[at]drwpf.com. My response time depends entirely on my workload.