Extension Function (2): Multicast Event

In my previous blog "Extension function (1): Extend" already Extension ' function ' function to implement Extend.

Follow the leads I ' ll talk about extension ' Function ' to implement multicast Event.

Some friends may familiar and listener model,some friends May is not.

But Event I believe these are no one none used.

In Js,we usually use blew the code to implement event.

vareventdemoclass= 

function () {
//constructor
}
Eventdemoclass.prototype = (function () {
// Private
return{
//public  
ondosomestaff:null,
dosomestaff:function () {
//some function code
if (this. Ondosomestaff) {This
. Ondosomestaff (Object,args);}}}
();
Varc=neweventdemoclass ();
C.ondosomestaff=function () {
alert ("Staff is done");
}
C.dosomestaff ()

It ' s easy and effective when just only one function to Regist.

But If we need regist multicast event as we used in C #.

What can we do?

As Usual,here is the core code.

Register Event Method//@param eventName: Event name//@param func: Registration method//@param executor: Execution context object if NULL, use default context 
        Function.prototype.AddEventListener = function (EventName, func, executor) {var eventfunc = function () {//Multicast event execution Critical method
        var eventarray = Arguments.callee.FunctionArray;
        var executorarray = Arguments.callee.Executor;
            for (var i = 0; i < eventarray.length i++) {var executor = executorarray[i];
            if (!executor) {executor = this;
        } eventarray[i].apply (executor, arguments); } if (!this[eventname] | |!this[eventname].
        Functionarray) {This[eventname] = Eventfunc; This[eventname].
        Functionarray = []; This[eventname].
    Executor = []; } This[eventname].
    Functionarray.push (func); This[eventname].
Executor.push (Executor);
//Unregister method//@param eventName: Event name//@param funchandle: Unregister Method Object If it is not the original object used for registration,//will not be able to cancel the action Function.prototype.RemoveEventListener = function (evEntname, Funchandle) {if (This[eventname] && this[eventname]. Functionarray) {var index = This[eventname].
        Functionarray.removeobject (Funchandle); if (index >= 0) {This[eventname].
        Executor.removeindex (index); }
    }
}

See more highlights of this column: http://www.bianceng.cnhttp://www.bianceng.cn/webkf/prototype/