Another way to implement a binding-computable properties in WPF

For example, there is a project in the WPF and the ViewModel in it, in which there are two properties of Price and Quantity, and computable property TotalPrice = Price * Quantity

Code

public class Order: BaseViewModel
    {
        private double _price;
        private double _quantity;
        public double Price
        {
            get {return _price; }
            set
            {
                if (_price == value)
                    return;
                _price = value;
                RaisePropertyChanged ( "Price");
            }
        }
        public double Quantity
        {
            get {return _quantity; }
            set
            {
                if (_quantity == value)
                    return;
                _quantity = value;
                RaisePropertyChanged ( "Quantity");
            }
        }
        public double TotalPrice {get {return Price * Quantity; }}
    }
    public class BaseViewModel: INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;
        protected virtual void RaisePropertyChanged (string propertyName)
        {
            var propertyChanged = PropertyChanged;
            if (propertyChanged! = null)
                propertyChanged (this, new PropertyChangedEventArgs (propertyName));
        }
    }

If Price will be changed in the code, the price changes are automatically displayed in the View, because ViewModel View report of Price Change by calling the event RaisePropertyChanged ( «Price»). Computed TotalPrice did not change in the View, because no one is RaisePropertyChanged ( «TotalPrice»). You can call RaisePropertyChanged ( «TotalPrice») in the same places where called RaisePropertyChanged ( «Price») and RaisePropertyChanged ( «Quantity»), but do not want to spread over a plurality of information on places that TotalPrice depends on Price and Quantity, and I would like to store this information in one place. To this end, a variety of people write dependency management, but let's see what is the minimum code is actually needed for this.