public WeakEventHandlerGeneric(H eventHandler, UnregisterDelegate <H> unregister)
{
_targetRef = new WeakReference((eventHandler as Delegate).Target);
_openHandler = (OpenEventHandler)Delegate.CreateDelegate(typeof(OpenEventHandler), null, (eventHandler as Delegate).Method);
_handler = CastDelegate(new LocalHandler(Invoke));
_unregister = unregister;
}
public WeakEventHandlerGeneric(H eventHandler, UnregisterDelegate <H> unregister)
{
this._targetRef = new WeakReference((eventHandler as Delegate).Target);
this._openHandler = (WeakEventHandlerGeneric <T, E, H> .OpenEventHandler)Delegate.CreateDelegate(typeof(WeakEventHandlerGeneric <T, E, H> .OpenEventHandler), null, (eventHandler as Delegate).Method);
this._handler = WeakEventHandlerGeneric <T, E, H> .CastDelegate(new WeakEventHandlerGeneric <T, E, H> .LocalHandler(this.Invoke));
this._unregister = unregister;
}
private void Invoke(object sender, TEventArgs e)
{
var target = (T)m_TargetRef.Target;
if (target != null)
{
m_OpenHandler.Invoke(target, sender, e);
}
else if (m_Unregister != null)
{
m_Unregister(m_Handler);
m_Unregister = null;
}
}
private void Invoke(object sender, E e)
{
T target = (T)_targetRef.Target;
if (target != null)
{
_openHandler.Invoke(target, sender, e);
}
else if (_unregister != null)
{
_unregister(_handler);
_unregister = null;
}
}
private void Invoke(object sender, E e)
{
T t = (T)((object)this._targetRef.Target);
if (t != null)
{
this._openHandler(t, sender, e);
return;
}
if (this._unregister != null)
{
this._unregister(this._handler);
this._unregister = null;
}
}
/// <summary>
/// Makes a property change handler weak
/// </summary>
/// <typeparam name="E"></typeparam>
/// <param name="eventHandler">The event handler.</param>
/// <param name="unregister">The unregister.</param>
/// <returns></returns>
public static PropertyChangedEventHandler MakeWeak(this PropertyChangedEventHandler eventHandler,
UnregisterDelegate <PropertyChangedEventHandler> unregister)
{
CheckArgs(eventHandler, unregister);
Type generalType = typeof(WeakPropertyChangeHandler <>);
var genericTypes = new[] { eventHandler.Method.DeclaringType };
var constructorTypes = new[]
{
typeof(PropertyChangedEventHandler),
typeof(UnregisterDelegate <PropertyChangedEventHandler>)
};
var constructorArgs = new object[] { eventHandler, unregister };
return
(((IWeakPropertyChangedEventHandler)
GetWeakHandler(generalType, genericTypes, constructorTypes, constructorArgs)).Handler);
}
/// <summary>
/// Makes a generic handler weak
/// </summary>
/// <typeparam name="TEventArgs"></typeparam>
/// <param name="eventHandler">The event handler.</param>
/// <param name="unregister">The unregister.</param>
/// <returns></returns>
public static EventHandler <TEventArgs> MakeWeak <TEventArgs>(this EventHandler <TEventArgs> eventHandler,
UnregisterDelegate <EventHandler <TEventArgs> >
unregister) where TEventArgs : EventArgs
{
CheckArgs(eventHandler, unregister);
Type generalType = typeof(WeakEventHandler <,>);
var genericTypes = new[] { eventHandler.Method.DeclaringType, typeof(TEventArgs) };
var constructorTypes = new[]
{
typeof(EventHandler <TEventArgs>),
typeof(UnregisterDelegate <EventHandler <TEventArgs> >)
};
var constructorArgs = new object[] { eventHandler, unregister };
return
(((IWeakEventHandler <TEventArgs>)
GetWeakHandler(generalType, genericTypes, constructorTypes, constructorArgs)).Handler);
}
public WeakPropertyChangeHandler(PropertyChangedEventHandler eventHandler, UnregisterDelegate <PropertyChangedEventHandler> unregister) : base(eventHandler, unregister)
{
}
public WeakEventHandler(EventHandler <E> eventHandler, UnregisterDelegate <EventHandler <E> > unregister)
: base(eventHandler, unregister)
{
}
