/// <summary>add handler for the .NET object:
/// create a dynamic delegate according to the given event type
/// add method body to the delegate
/// in the method body call DefaultDotNetHandler which will handle the event</summary>
/// <param name="eventName"> name of the event</param>
/// <param name="objectToHook"> object to hook</param>
/// <param name="objectEvents"> once registered, events are added to this collection</param>
/// <param name="reportErrors"> indicates whether to log errors while hooking event. There are some
/// default events that are hooked for each .NET control (see DNControlEvents._standardControlEvents).
/// Errors occurring while hooking these events should not be reported.</param>
/// TODO handle static events
internal static void addHandler(String eventName, Object objectToHook, DNObjectEventsCollection.ObjectEvents objectEvents, bool reportErrors)
{
//subscribe for events only once , check if handler already added
if (objectEvents.delegateExist(eventName))
{
return;
}
Type type = objectToHook.GetType();
// Get an EventInfo representing the event, and get the type of delegate that handles the event.
EventInfo eventInfo = type.GetEvent(eventName);
if (eventInfo != null)
{
// Get the "add" accessor of the event and invoke it late-bound, passing in the delegate instance.
// This is equivalent to using the += operator in C#, or AddHandler in Visual Basic.
// The instance on which the "add" accessor is invoked is the form;
// the arguments must be passed as an array.
MethodInfo addHandler = eventInfo.GetAddMethod();
Delegate eventHandler = null;
try
{
#if !PocketPC
eventHandler = createDynamicDelegate(objectToHook.GetHashCode(), eventInfo);
#else
if (objectToHook is Control)
{
eventHandler = DNControlEvents.getPredefinedEvent(eventName);
}
#endif
try
{
addHandler.Invoke(objectToHook, new Object[] { eventHandler });
}
catch (Exception e)
{
if (e is TargetInvocationException && e.InnerException != null)
{
throw e.InnerException;
}
else
{
throw e;
}
}
objectEvents.add(eventName, eventHandler);
}
catch (Exception exception)
{
if (reportErrors)
{
DNException dnException = Manager.GetCurrentRuntimeContext().DNException;
dnException.set(exception);
}
}
}
else
{
if (reportErrors)
{
Events.WriteExceptionToLog(String.Format("Event type \"{0}\" not supported", eventName));
}
}
}
/// <summary>
//This function registers "HandleDNControlValueChanged" to the event
//specified by the user for DN control property change.
/// </summary>
/// <param name="eventName">Event to be registered</param>
/// <param name="obj">object on which, event will be registered</param>
internal static void AddDNControlValueChangedHandler(object objectToHook, String eventName)
{
Control ctrl = (Control)objectToHook;
DNObjectEventsCollection.ObjectEvents objectEvents = DNManager.getInstance().DNObjectEventsCollection.checkAndCreateObjectEvents(ctrl);
//DNControlValueChangedDelegate and DNControlValueChangedEventName should be initialized only once. If initialized second time, assert.
//Debug.Assert(objectEvents.DNControlValueChangedDelegate == null && objectEvents.DNControlValueChangedEventName == null);
Type type = ctrl.GetType();
//Get an EventInfo representing the event, and get the type of delegate that handles the event.
EventInfo eventInfo = type.GetEvent(eventName);
if (eventInfo != null)
{
// Get the "add" accessor of the event and invoke it late-bound, passing in the delegate instance.
// This is equivalent to using the += operator in C#, or AddHandler in Visual Basic.
// The instance on which the "add" accessor is invoked is the form;
// the arguments must be passed as an array.
MethodInfo addHandler = eventInfo.GetAddMethod();
Delegate eventHandler = null;
try
{
if (objectEvents.DNControlValueChangedDelegate != null)
{
Debug.Assert(objectEvents.DNControlValueChangedEventName == eventName);
eventHandler = objectEvents.DNControlValueChangedDelegate;
}
else
{
eventHandler = createDynamicDelegateForDNCtrlValueChangedEvent(ctrl.GetHashCode(), eventInfo);
//Add delegate(event handler) to object events.
objectEvents.DNControlValueChangedDelegate = eventHandler;
//Add event name to object events.
objectEvents.DNControlValueChangedEventName = eventName;
}
try
{
addHandler.Invoke(objectToHook, new Object[] { eventHandler });
}
catch (Exception e)
{
if (e is TargetInvocationException && e.InnerException != null)
{
throw e.InnerException;
}
else
{
throw e;
}
}
}
catch (Exception exception)
{
DNException dnException = Manager.GetCurrentRuntimeContext().DNException;
dnException.set(exception);
}
}
else
{
Events.WriteExceptionToLog(String.Format("Event type \"{0}\" not supported", eventName));
}
}
