C# - Implement property observation afterwards

Question

I have a question about the observation of properties of an object.

For example, I have a class like this:

public class MyProperties
{
  public string Prop1 { get; set; }
  public int Prop2 { get; set; } 
}

My wish is to get a notification if one of the properties of MyProperties are changed. My vision is something like this:

//I have an instance
MyProperties Prop = new Myproperties();
//And add a listener to the properties
Prop.Prop1.AddNotification(APropertyChanged);
Prop.Prop2.AddNotification(APropertyChanged);

//I have a eventhandler in my code
public void (object Sender, EventArgs e)
{
  //Sender is the Property
}

I don't want to change any code in MyProperties. Is there any way to achive something like this .. or is this idea totally idiotic?

Answer 1

Here is my solution. Thanks to the tip of @romain-aga.

Fody PropertyChanged allows to change the code of properties during compilation. If I have the class:

public class MyProperties
{
    public string Prop1 { get; set; }
    ...
}

Fody would compile this code:

public class MyProperties
{
    string prop1;
    public string Prop1
    {
        get { return prop1; }
        set
        {
            if (value != prop1)
            {
                prop1 = value;
                OnPropertyChanged("Prop1");
            }
        }
    }
    ...
}

Via reflection, it is possible to add a method to the generated PropertyChanged event:

EventInfo Event = typeof(MyProperties).GetEvent("PropertyChanged");
MethodInfo Method = //The methode of the handler you want
Delegate Handler = Delegate.CreateDelegate(Event.EventHandlerType, this, Method);
Event.AddEventHandler(IntanceOfMyProperties, Handler);