jquery onSubmit, onComplete, etc

I notice that a lot of tools built in jQuery, and particularly those that use some kind of ajax, have hooks such as onSubmit, onComplete, etc.

Is there a name for this practice and the conventions that ch开发者_开发问答aracterize it?

Is the culture of this practice part of the jQuery community, or is it a larger javascript phenomenon?

Can you recommend a guide to building tools that utilize this methodology?

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Yep it's called the Observer design pattern. It's not isolated to JQuery or even JavaScript for that matter. Many design patterns can be implemented into most programming languages.

DevShop is a framework of design patterns for javascript. Their Observer pattern looks like this:

OBSERVER

(function(){
    DevShop.Me({
        Observer:function(obj){
            var observer=function(){
                this.onRegister=function(){};
                this.notify=function(eventName,observable){
                    this.observable=observable;
                    if(typeof this[eventName]==="function")
                        try{this[eventName]();}catch(e){}
                };
            };
            return DevShop.SingletonFactory({extend:observer,instance:obj});
        }
    });
})();

OBSERVABLE

(function(){
    DevShop.Me({
        Observable:function(obj){
            var observable=function(){
                this.observers=[];
                this.addObserver=function(o){
                    if(typeof o==="function"||typeof o==="object"){
                        if(typeof o.notify==="function"){
                            this.observers.push(o);
                            if(typeof o.onRegister==="function")
                                try{o.onRegister();}catch(e){}
                        }
                    }
                };
                this.notifyObservers=function(eventName){
                    var size=this.observers.length;
                    for(var x=0;x<size;x++){
                        try{
                            this.observers[x].notify(eventName,this);
                        }catch(e){}
                    }
                };
            };
            return DevShop.SingletonFactory({extend:observable,instance:obj});
        }
    });
})();

You can read more about the Observer design pattern here: http://en.wikipedia.org/wiki/Observer_pattern