Hi there,

I've got a question about a Silverlight WCF Databinding pattern:

There are many examples about how to bind data using {Binding} expressions in XAML, how to make async calls to a WCF service, set the DataContext property of a element in the UI, how to use ObservableCollections and INotifyPropertyChanged, INotifyCollectionChanged and so on.

Background: I'm using the MVVM pattern, and have a Silverlight ItemsControl, whose ItemsSource is set to an ObservableCollection property on my ViewModel object. My view is of course the XAML which has the {Binding}. Say the model object is called 'Metric'. My ViewModel periodically makes calls to a WCF service that returns ObservableCollection. MetricInfo is the data transfer object (DTO).

My question is two-fold:

1. Is there any way to avoid copying each property of MetricInfo to the model class - Metric?
2. When the WCF calls completes, is there any way to make sure I sync the items which are in both my local ObservableCollection and the result of the WCF call - without having to first clear out all the items in the local collection and then add all the ones from the WCF call result?

thanks, Krishna