How to keep some context attached to a JavaScript event handler?

Quizz JavaScript - reponse : objet et abonnement d'evenement

Atteint de Javascriptite aiguë [Cyril DURAND] — Mon, 13 Aug 2007 23:46:09 GMT

Voici les réponses au Quizz JavaScript : objet et abonnement d'événement Le problème était encore à cause

Quizz JavaScript : réponse gestionnaire d'evenements et boucle

Atteint de Javascriptite aiguë [Cyril DURAND] — Sun, 12 Aug 2007 14:55:22 GMT

Voici la réponse au Quizz JavaScript - gestionnaire d'evenements et boucles . Pour rappel la question

re: How to keep some context attached to a JavaScript event handler?

Bertrand Le Roy — Tue, 17 Jul 2007 18:00:38 GMT

t3knomanser: yes, what you're not seeing is that this is implemented using closures. If you're confortable with using closures directly, that's fine but you need to be careful as you may inadvertently attach more context than you need and even create hard to find memory leaks in IE. The methods presented here are more convenient, they hide a concept that is difficult or unknown to many developers who are new to JavaScript, and they only capture in the closure what little context *you* decide is useful.

re: How to keep some context attached to a JavaScript event handler?

t3knomanser — Tue, 17 Jul 2007 13:17:19 GMT

Is there any reason to not just use closures? This seems like a pretty uninteresting method. Closures do this, and a bunch more. Is there something I'm not seeing?

re: How to keep some context attached to a JavaScript event handler?

Joel Rumerman — Mon, 04 Jun 2007 21:22:01 GMT

Hey Bertrand, Hope all is well. I've used this technique before for web services as Sean mentioned above and for attaching events to external objects (i.e. the page request manager). Thx for confirming that this was the correct way to maintain context with the current object. What else can this technique do for us (the advanced topics you hinted at)? I'd love a follow up post on this topic. Thx, Joel

re: How to keep some context attached to a JavaScript event handler?

Sean Kinsey — Wed, 11 Apr 2007 16:36:01 GMT

This is also usefull when calling webservices with a callback handler. By using a delegate the callback will be executed in the same context as the function calling the webservice, something that is extremely usefull when calling webservices from within custom objects.

re: How to keep some context attached to a JavaScript event handler?

Bertrand Le Roy — Wed, 11 Apr 2007 15:50:56 GMT

Muhammad: you'll have to ask Telerik...

re: How to keep some context attached to a JavaScript event handler?

Muhammad Mosa — Wed, 11 Apr 2007 15:40:35 GMT

Well, I built an AJAX Control, it is a simple Custom ComboBox. if acctually uses javascript extensions provided by ASP.NET AJAX Framwork to show and hide and select items from a simle list control "<select>". this control is working fine with UpdatePanel as it rais post back and also . I tried to use it withing Telerik Ajax Panel, and with Telerik Ajax Manager. I'me not sure if you used them before. With Telerik Ajax Manager displays a Javascript error and with Ajax Panel it is not updating panel content as well as stops to response to javascript events e.g, click on text box to show the list box etc...

Do you have any idea about that!?

re: How to keep some context attached to a JavaScript event handler?

Aleksey Fomichenko — Wed, 11 Apr 2007 06:51:52 GMT

Great article! This really helps.

What I used to do before reading this post is:

var self = this;

CallWebServiceMethod(function(results) { self.OnComplete(results); });