WeakEventDemo.cs

public class DummyObject
    {
        public void Touch()
        {
            if (_Touched != null)
                this._Touched(this, EventArgs.Empty);
        }

        EventHandler _Touched;
        public event EventHandler Touched
        {
            add {
                var mi = value.Method;

                WeakEventHandler.Register(
                    this,
                    value.Target,
                    (s, h) => s._Touched += h,
                    (s, h) => s._Touched -= h,
                    (source, sender, args) => mi.Invoke(source, new [] { sender, args} )
                    );
                }
            remove { _Touched -= value;  }
        }
        
    }