MVVM and INotifyPropertyChanged Issue

Question

I have a big problem with MVVM design. I am trying to catch every PropertyChanged of my inner nested objects, including futhermore propertchanged of their nested objects, in

Answer 1

There is no clear constraint about what PropertyName should contains in PropertyChangedEventArgs.

See Subscribe to INotifyPropertyChanged for nested (child) objects.

Here is an example :

class A : BaseObjectImplementingINotifyPropertyChanged {

  private string m_name;
  public string Name {
    get { return m_name; }
    set {
      if(m_name != value) {
        m_name = value;
        RaisePropertyChanged("Name");
      }
    }
  }
}

class B : BaseObjectImplementingINotifyPropertyChanged {

  private A m_a;
  public A A {
    get { return m_a; }
    set {
      if(m_a != value) {
        if(m_a != null) m_a.PropertyChanged -= OnAPropertyChanged;
        m_a = value;
        if(m_a != null) m_a.PropertyChanged += OnAPropertyChanged;
        RaisePropertyChanged("A");
      }
    }
  }

  private void OnAPropertyChanged(object sender, PropertyChangedEventArgs e) {
    RaisePropertyChanged("A." + e.PropertyName);
  }

}


B b = new B();
b.PropertyChanged += (s, e) => { Console.WriteLine(e.PropertyName); };
b.A.Name = "Blah"; // Will print "A.Name"