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Use the FastObservableCollection
The FastObservableCollection does not raise events for every item, but only invokes events for the complete range of items added to or removed from the collection.
When modifying a large collection of items, it is not required to raise change events for each added / removed value. Therefore the FastObservableCollection will disable change notifications until the full collection modification is done and then raise the change events just once.
Implementing IDependencyPropertySelector
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