js中dispatchEvent后的处理

[zimu312500]

我借用了别人的一个对象用来继承，使自己的DIV对象具有订阅事件，下发事件的功能，代码如下，现在的问题是我想在function函数里面下发，在<script for=map event="函数名">中捕获，我不大清楚js的事件是怎么进行下发的，请教各位大侠，非常感谢！！！

<script>
//原型：EventManager是一个重要的原型，它用来赋予对象自定义事件的能力
//当对象类型的原型继承EventManager时，对象具有定义、分派和捕捉事件的能力
//EventManager有四个重要的方法dispatchEvent、captureEvent、addEventListener和removeEventListener
/*
提示：您可以先修改部分代码再运行
我认为还是通过dispatchEvent发布事件代理，addEventListener捕捉和注册事件，这样比较符合设计原则，可读性也比较强
貌似W3C的DOM-Level-2其实也是采用这种模式设计DOM对象的基础类型的......*/


function EventManager()
{
	this.dispatchEvent = function(eventType, eventArgs)
	{
		eventArgs = eventArgs || {};
		var events = this["on"+eventType];
		var called = 0;

		if(events && typeof(events) == "function")
			events = [events];

		if(!eventArgs.type) eventArgs.type = eventType;
		//阻止默认动作的执行
		eventArgs.preventDefault = function()
		{
			eventArgs.defaultOp = null;
		}
		//阻止事件起泡
		eventArgs.stopPropagation = function()
		{
			eventArgs.cancelBubble = true;
		}
		var $pointer = this;
		if(events)
		{
			for(var i = 0; i < events.length; i++)
			{

				setTimeout(
					(function(i){
						var evt = events[i];
						var len = events.length;
						var capturer = events.capturer;
						var capturerName = events.capturerName;
						return	function(){
							called++;

							var ret = evt.call($pointer,eventArgs);
							//如果有捕获事件的方法，并且没有阻止事件气泡，在最后一个事件处理程序结束之后调用它
							if(!eventArgs.cancelBubble && called == len && capturer && capturerName && capturer[capturerName])
							{
								setTimeout(function(){
										capturer[capturerName](eventArgs)
									},1)
							}
							//如果定义了默认动作，在最后一个事件处理程序结束之后执行它
							if(called == len && eventArgs.defaultOp) 
							{
								eventArgs.defaultOp.call($pointer, eventArgs);
							}
							return ret;
						}
					})(i), 1
				);
			}
		}
		else if(eventArgs.defaultOp)
		{
			eventArgs.defaultOp.call($pointer, eventArgs);
		}
	}
	this.fireEvent = this.dispatchEvent;
	this.captureEvents = function(target, eventType, capturerName, closure)
	{
		if(capturerName instanceof Function)
		{
			closure = capturerName;
			capturerName = null;
		}
		capturerName = capturerName || "on" + eventType;
		target["on"+eventType] = target["on"+eventType] || [function(){}];
		var events = target["on"+eventType];
		if(typeof(events) == "function")
		{
			target["on"+eventType] = [events];
		}

		target["on"+eventType].capturer = this;
		target["on"+eventType].capturerName = capturerName;

		if(closure)
			this[capturerName] = closure;
	}

	this.addEventListener = function(eventType, closure)
	{
		if(this["on"+eventType] == null)
		{
			this["on"+eventType] = [];
		}
		var events = this["on"+eventType];
		if(events && typeof(events) == "function"){
			this["on"+eventType] = [events];		
			events = this["on"+eventType];
		}
		events.push(closure);
		return closure;
	}

	this.removeEventListener = function(eventType, closure)
	{
		var events = this["on"+eventType];
		if(events && typeof(events) == "function")
			events = [events];		
		
		for(var i = 0; i < events.length; i++)
		{
			if(events[i] == closure)
				events.splice(i, 1);
		}
		return closure;
	}
}
</script>
<script src="http://ditu.google.com/maps?file=api&v=2&key=abcdefg" type="text/javascript"></script>  
<script type="text/javascript"> 
var newGontrol = new GSmallMapControl();   
var map = null;  //创建并初始化地图      
function load() 
{        
	if (GBrowserIsCompatible()) 
	{          
		var mapdiv = document.getElementById("mapdiv");
		
		EventManager.call(mapdiv);
		map = new GMap2(mapdiv);          
		map.addControl(newGontrol);          
		map.setCenter(new GLatLng(39.92, 116.385), 15);     
		
		/*mapdiv.onchange = function(evt){
		
			evt.stopPropagation();              //阻止事件被捕获
			alert("event capturing stopped!");
		}   */ 
		mapdiv.addEventListener("change",function(evt)          //高级的事件注册方式
		{
			alert("oldValue:"+evt.oldValue);
			alert("newValue:"+evt.newValue);
		})
		
		/*mapdiv.captureEvents(mapdiv,"change",null, function(evt){
		alert("a.a has changed from " + evt.oldValue + " to " + evt.newValue);
		});;*/
		
		mapdiv.dispatchEvent("change", {oldValue:1, newValue:2});
		
		
	 }      
}    

</script>   
</head>   
<body onload="load()" onunload="GUnload()">     
<div id="mapdiv" style="width: 500px; height: 300px"></div>   
</body> 
</html> 
<script language="javascript" for=mapdiv event="onchange(evt)">
	alert("oldValue:"+evt.oldValue);
	alert("newValue:"+evt.newValue);
</script>

代码有点长，我想达到的目的就是想让最后的event捕获到我函数中下发的事件，求求求

[zimu312500]

uyupupupupupup

[gouxiongyaya]

帮你顶一下吧，不太懂。。。