Peter Ritchie's MVP Blog

Hmm. Nice that Specialized.StringCollection is not going to be removed (well it seems like it). I quite like how easy it is when using it in My.Settings.

According to the comments section of the cited BCL blog entry, there are no plans to remove non-generic collections from the .NET framework.  This removal only applies to Silverlight.

And it's a good thing too, since there are situations that require non-generic collections.

For example, the SoapFormatter class doesn't support serializing generic collections.  Currently, an easy way to persist data to a file (for example), is to add the data to a non-generic dictionary (like ListDictionary, Hashtable, etc), and simply serialize it to a file via SoapFormatter.  This results in an easy to read XML file containing the data (and the file is Soap conformant).  To deserialize the data from the file, use SoapFormatter to deserialize it into a non-generic dictionary, then retrieve the data from the dictionary.  This couldn't be done with a generic dictionary because A) they can only take values of a specific type, and B) SoapFormatter doesn't support serializing generic collections.  Using Dictionary<Object> as a generic dictionary would get around (A) but not (B).  (Note that the XmlSerializer doesn't support serializing IDictionary collections, so you couldn't use that either.)

That's just one example of many times were non-generic collections are needed.  But they should be removed for Silverlight to keep Silverlight as small as possible.

It's really a headache trying to migrate to Silverlight!

class Person

{

protected Hashtable _lstProperties;

public Hashtable Properties <<-- Property type cannot be known apriori! It's template class!

{

get { return _lstProperties; }

set { _lstProperties = value; }

}

}

And property really is a template class ...

class Property<T>

{

...

}

And Silverlight stipulates that every collection be System.Collections.Generic - this means even if I hand out the source code, it can't be consumed from Silverlight.