Do you mean how to create a collection property on a custom class? If that is the case then it should be like any .Net class (you could use something like Collection<T> and expose it as a property.
If that was not the question, then I think can you explain more about what you are trying to do?
Not sure what you mean but custom collection property editor either
In ASP.NET custom control i use this property (MyEditor call My custom Windows Form where i select and set items):
public List<MyItem> Items
My question is how i create it in SilverLight application.
Currently we do not support designers or design time –only behaviors. We are looking to address our design story in future versions. Currently in VS Orcas the designer is actual WPF, not Silverlight, rendering the XAML.
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