Lambda Expression casting to Observable Collection

If I have an object of type Person and it has a navigation property of PersonAddressJoin which then has addresses.

PersonResults= new ObservableCollection<Person>(_op.Entities.OfTy开发者_如何学Cpe<Person>());

and I want to then take the PersonAddressJoin navigation property and put that into an object. so i have an ObservableCollection AddressList

AddressList = PersonResults.SelectMany(x => x.PersonAddressJoins);

when i do it this way I get a message that says I cant cast an IEnumberable to an ObservableCollection.?

Can someone help me get that navigation property into this object...thanks

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The result of SelectMany is an IEnumerable. Untested, but try:

AddressList = new ObservableCollection<PersonAddressJoins>(PersonResults.SelectMany(x => x.PersonAddressJoins));