Javascript处理DOM元素事件实现代码

/*
* 功能：事件处理
* Author：LQB
* 时间：2009-1-4
* #include JCore.js
*/
var JEvents = function(){
this.events={};
this.addEvent = function(o){//添加事件
if(typeof o == 'string'){/*strArg1,strArg2……的方式传递参数*/
for(var i = 0, a = arguments, v; v = a[i]; i++){
v = v.toString().toLowerCase();
var enFX = v.indexOf("on")==0 ? v.substr(2) : v;
if(!this.events[enFX]){
this.events[enFX] = true;
}
}
}else{
JCore.apply(this.events, o,false);
}
};
this.addListener = function(eventName,fn,scope/*,Args……*/){//为事件添加处理方法
if(typeof(eventName)!="string"|| eventName.lenght==0)return;
if(typeof(fn)!="function")return;
eventName = eventName.toString().toLowerCase();
var enFX = eventName.indexOf("on")==0 ? eventName.substr(2) : eventName;
if(!this.events[enFX]){
throw "Error! Event /"" + eName + "/" doesnt exist."
}
var sp = scope||window;
var callArgs = Array.prototype.slice.call(arguments, 3);//从第4个参数开始
callArgs = typeof(callArgs)!="undefined"?callArgs:[];
var delegate = fn.createDelegate(callArgs,sp);//JCore支持
//为fn方法创建标记，在删除事件时使用
if(!fn.uid) {
var time = new Date();
fn.uid= ""+time.getMinutes()+time.getSeconds()+time.getMilliseconds();
}
//标记委托，在删除事件绑定时使用
delegate.uid = getCacheAttName(enFX,fn.uid);
if(typeof(this.events[enFX])!="object")
this.events[enFX]=[];
this.events[enFX].push(delegate);//把方法添加到事件列表中
};
this.removeListener = function(eventName,fn){//移除事件绑定
if(eventName && fn){
eventName = eventName.toString().toLowerCase();
var enFX = eventName.indexOf("on")==0?eventName.substr(2):eventName;
var AttName = getCacheAttName(enFX,fn.uid);
if(typeof(this.events[enFX])=="object"){//存在这个事件
var functions = this.events[enFX];
for(i=0;i<functions.length;i++){//依次查找每个方法
if(functions[i].uid===AttName){//找到，删除
this.events[enFX].remove(functions[i]);
break;
}
}
}
}
}
this.fireEvent = function(eName,eventArg){//触发事件
eName = eName.toString().toLowerCase();
var enFX = eName.indexOf("on")==0 ? eName.substr(2) : eName;
var Arg = new Array();
if(typeof(eventArg)!="undefined"){
if(typeof(eventArg)=="array") Arg=eventArg;
else Arg.push(eventArg);
}
if(typeof(this.events[enFX])=="object"){//存在此事件，同时添加了事件处理方法
var functions = this.events[enFX];
for(i=0;i<functions.length;i++){//依次触发所有方法
functions[i].apply(window,Arg);
}
}
}
/*---------------------------------------私有方法--------------------------------------*/
var getCacheAttName = function(eventName,fnuid){
return "handle-"+eventName+"-"+fnuid;
}
}
/*------------------------------------------------------以下是静态方法，用于处理DOM element的事件-----------------------------------------*/
var JEventsExtendMethod = {
cache : {//时间处理缓存，用于标记各个事件处理方法，在删除事件时使用
eventCache : {},
setCache : function(el,Name,value){
if(typeof(this.eventCache[el])!="object"){
this.eventCache[el]={length :1};
}
this.eventCache[el][Name]=value;
this.eventCache[el].length++;
},
getCache : function(el,Name){
if(typeof(this.eventCache[el]) =="object")
return this.eventCache[el][Name];
else
return null;
},
removeCache : function(el,Name){
if(typeof(this.eventCache[el]) =="object"){
delete this.eventCache[el][Name];//删除属性
this.eventCache[el].length--;
}
if(this.eventCache[el] && this.eventCache[el].length ==1)//清除
delete this.eventCache[el];
}
},
getCacheAttName : function(eventName,fnuid){
return "handle-"+eventName+"-"+fnuid;
},
bind : function(el,eventName,fn,scope/*,Args……*/){//为elment添加事件处理方法
if(typeof(el)=="undefined"||el==null)return;
if(typeof(eventName)!="string"|| eventName.lenght==0)return;
if(typeof(fn)!="function")return;
var indexOfon = eventName.toString().toLowerCase().indexOf("on");
var enIE = indexOfon==0?eventName:"on"+eventName;
var enFX = indexOfon==0?eventName.substr(2):eventName;
var sp = scope||window;
var callArgs = Array.prototype.slice.call(arguments, 4);//从第5个参数开始
callArgs = typeof(callArgs)!="undefined"?callArgs:[];
var delegate = fn.createDelegate(callArgs,sp);//JCore支持
if (el.addEventListener){//Mozilla系列,按队列顺序执行
el.addEventListener(enFX, delegate, false);//第三个参数与触发方式相关
} else if (el.attachEvent){//非Mozilla系列，按堆栈顺序执行(后加的事件先执行)
el.attachEvent(enIE, delegate);
}
//为fn方法创建标记，在删除事件时使用
if(!fn.uid) {
var time = new Date();
fn.uid= ""+time.getMinutes()+time.getSeconds()+time.getMilliseconds();
}
if(!el.id){
el.id = JCore.id(el,null);
}
//标记委托，在删除事件绑定时使用
var AttName = this.getCacheAttName(enFX,fn.uid);
this.cache.setCache(el.id,AttName,delegate);
},
unbind : function(el,eventName,fn){//为elment解除事件绑定
if(typeof(el)=="undefined"||el==null)return;
var indexOfon = eventName.toString().toLowerCase().indexOf("on");
var enIE = indexOfon==0?eventName:"on"+eventName;
var enFX = indexOfon==0?eventName.substr(2):eventName;
var AttName = this.getCacheAttName(enFX,fn.uid);
var delegate = this.cache.getCache(el.id,AttName);
if(delegate){
if (el.removeEventListener){//Mozilla系列
el.removeEventListener(enFX, delegate, false);
} else if (el.detachEvent){//非Mozilla系列
el.detachEvent(enIE, delegate);
}
}
//删除事件缓存
this.cache.removeCache(el.id,AttName);
}
}
JCore.apply(JEvents,JEventsExtendMethod);
/*--------------------------------对event的参数包装---------------------------------*/
var JEventWrap = function(event){
this.xtype="EventWrap";
this.data=null;
this.srcElement = null; //发生事件的文档元素
this.button = null; //[FX:0-左键，1-中间键，2-右键][IE:1-左键，2-右键，4-中键](仅对onmousedown, onmouseup,onmousemove有效)
this.type = null;
this.clientX = 0; //鼠标指针相对客户区或浏览器窗口的X坐标(标准属性)
this.clientY = 0; //鼠标指针相对客户区或浏览器窗口的Y坐标(标准属性)
this.offsetX = 0; //鼠标指针相对于源元素的X坐标(兼容属性)(IE)
this.offsetY = 0; //鼠标指针相对于源元素的Y坐标(兼容属性)(IE)
this.screenX = 0; //鼠标指针相对于用户显示器的左上角X坐标(兼容属性)(FX)
this.screenY = 0; //鼠标指针相对于用户显示器的左上角Y坐标(兼容属性)(FX)
this.altKey = false; //是否Alt键
this.ctrlKey = false; //是否Ctrl键，
this.shitfKey = false; //是否Shift键
this.keyCode = 0;
this.originaEvent = null; //未包装的原始事件对象
/*----构造-----*/
if(event){
if(event.srcElement){//IE
this.srcElement = event.srcElement;
this.offsetX = event.offsetX;
this.offsetY = event.offsetY;
this.button = event.button;
}
else{
this.srcElement = event.target;
this.offsetX = event.clientX - event.target.offsetLeft;
this.offsetY = event.clientY - event.target.offsetTop;
}
this.type = event.type;
this.altKey = event.altKey;
this.ctrlKey = event.ctrlKey;
this.shitfKey = event.shitfKey;
this.clientX = event.clientX;
this.clientY = event.clientY;
this.screenX = event.screenX;
this.screenY = event.screenY;
this.keyCode = event.keyCode;
this.originaEvent = event;
}
}