MVVM-Light PropertyChanged ViewModelBase

I would like to understand how the MVVM light toolkit raises the PropertyChanged event.

I have a feeling that this may be obvious... but I can't satisfy my curiousity without 100% clarity!

I know that this event is raised for each RaisePropertyChanged called, but I'm confused as to why PropertyChanged is raised when the HasValidationErrors property is changed as we开发者_JS百科ll?

Thanks, Richard

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When it comes to ViewModels or any class that implements INotifyPropertyChanged it is part of the contract that every property should raise the event when the property value changes. This way there is no unexpected behavior.