Question

I am implementing INotifyPropertyChanged and as part of that interface I have the member

public event PropertyChangedEventHandler PropertyChanged;

I have the following code for when some property gets changed –

public string FavoriteColor
    {
        get { return this.favoriteColor; }
        set
        {
            if (value != this.favoriteColor)
            {
                this.favoriteColor = value;
                **if (this.PropertyChanged != null)**
                {
                    this.PropertyChanged(this, new PropertyChangedEventArgs("FavoriteColor"));
                }
            }
        }
    }

Now, I have never set the PropertyChanged variable anywhere in my code, yet if I put a breakpoint at this line it shows that PropertyChanged does have a value. So how is it getting set?

Answer 1

If you bind to the property the binding system subscribes to the event.