<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">
<html xmlns="">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title></title>
</head>
<body>
<div>
<div></div>
</div>
<script type="text/javascript">
(function(doc,undefined){
function now(){
return +new Date;
};
var win = this,
expando = "jQuery" + now(),
uuid = 0,
cache = {};
win.data = function(elem, name, data){
var id = elem[expando];
if(!id)
id = elem[expando] = ++uuid;
if(name&&!cache[id])
cache[id] = {};
if(data !== undefined)
cache[id][name] = data;
return name
? cache[id][name]
: id;
}
win.removeData = function(elem, name){
var id = elem[expando];
if (name){
if (cache[id]) {
delete cache[id][name];
name = "";
for ( name in cache[ id ] )
break;
if ( !name )
removeData(elem);
}
}else{
try {
delete elem[expando];
} catch(e){
if ( elem.removeAttribute )
elem.removeAttribute( expando );
}
delete cache[id];
}
}
win.each = function( object, callback, args ) {
var name, i = 0, length = object.length;
if ( args ) {
if ( length === undefined ) {
for ( name in object )
if ( callback.apply( object[ name ], args ) === false )
break;
} else
for ( ; i < length; )
if ( callback.apply( object[ i++ ], args ) === false )
break;
} else {
if ( length === undefined ) {
for ( name in object )
if ( callback.call( object[ name ], name, object[ name ] ) === false )
break;
} else
for ( var value = object[0];
i < length && callback.call( value, i, value ) !== false; value = object[++i] ){}
}
return object;
}
win.gevent = {
guid : 1,
add : function (elem, types, handler){
if ( elem.nodeType == 3 || elem.nodeType == 8 )
return;
if ( elem.setInterval && elem != window )
elem = window;
//给函数一个唯一标识的索引 方便后面删除该事件
if ( !handler.guid )
handler.guid = this.guid++;
//获得该元素的events handle 下的数据
var events = data(elem, "events") || data(elem, "events", {}),
handle =data(elem, "handle") || data(elem, "handle", function(){
//gevent.handle才是各种行为触发后会执行的函数
gevent.handle.apply(arguments.callee.elem, arguments);
});
handle.elem = elem;
//遍历事件名 因为可以是 click mouseover
each(types.split(/\s+/), function(index, type) {
var namespaces = type.split(".");
//获得事件名
type = namespaces.shift();
//去掉点后面的东西 是个特殊的命名 在删除的时候可以指定删除他 如 click.d
//用事件的type 记录住这个特殊的命名
handler.type = namespaces.slice().sort().join(".");
//获得该事件是否已经存在events 这个对象里面了
var handlers = events[type];
//如果不存在该事件 给元素绑定该事件
if (!handlers) {
handlers = events[type] = {};
if (elem.addEventListener)
elem.addEventListener(type, handle, false);
else if (elem.attachEvent)
elem.attachEvent("on" + type, handle);
}
//吧函数放到元素的该事件的列表里面
handlers[handler.guid] = handler;
});
elem = null;
},
remove: function(elem, types, handler) {
if ( elem.nodeType == 3 || elem.nodeType == 8 )
return;
//获取这个元素的所有行为列表 如 {click:{},mouseocer:{}}
var events = data(elem, "events"), ret, index;
if(events){
//如果没出入行为类型 则删除这个元素的所有事件
//如果传入的是.xx这种形式的 把所有行为的包含.xx命名的全部干掉
if ( types === undefined || (typeof types === "string" && types.charAt(0) == ".") ){
for ( var type in events )
this.remove( elem, type + (types || "") );
}else{
//不知道干嘛的
if ( types.type ) {
handler = types.handler;
types = types.type;
}
//因为删除事件可以一次支持删除多个 如click mouseover 所有要遍历删除
each(types.split(/\s+/),function(index, type){
var namespaces = type.split(".");
type = namespaces.shift();
var namespace = RegExp("(^|\\.)" + namespaces.slice().sort().join(".*\\.") + "(\\.|$)");
if ( events[type] ) {
//如果传了第3个参数 函数 则删除这个事件
if ( handler )
delete events[type][handler.guid];
else{
//遍历中个这个的所有行为
for ( var handle in events[type] ){
// Handle the removal of namespaced events
//删除有特殊命名的函数
//如果没有特殊命名 正则 则是/^|..|$/ 可以匹配空 所以也能删除掉没有特殊命名的函数
if ( namespace.test(events[type][handle].type) )
delete events[type][handle];
}
}
}
for ( ret in events[type] ) break;
//如果events[type]变成空的了 也就是{} 删除这个元素的的绑定事件
if ( !ret ) {
if (elem.removeEventListener)
elem.removeEventListener(type, data(elem, "handle"), false);
else if (elem.detachEvent)
elem.detachEvent("on" + type, data(elem, "handle"));
ret = null;
delete events[type];
}
});
}
for ( ret in events ) break;
//如果发现元素的整个events都是空的了
//清空掉handle 并且清空掉他所有的引用
if ( !ret ) {
var handle = data( elem, "handle" );
if ( handle ) handle.elem = null;
removeData( elem, "events" );
removeData( elem, "handle" );
}
}
},
handle : function(event){
var all, handlers;
//包装event
event = arguments[0] = gevent.fix( event || window.event );
event.currentTarget = this;
//这里的........
var namespaces = event.type.split(".");
event.type = namespaces.shift();
all = !namespaces.length;
var namespace = RegExp("(^|\\.)" + namespaces.slice().sort().join(".*\\.") + "(\\.|$)");
//取这个元素的该行为 的 事件列表
handlers = (data(this, "events") || {} )[event.type];
//遍历这个事件列表 执行该执行的东西
for ( var j in handlers ) {
var handler = handlers[j];
if ( all || namespace.test(handler.type) ) {
// Pass in a reference to the handler function itself
// So that we can later remove it
// jq上的注释是是这么写的 把event的handler 引用这个事件 方便之后移除
// 但是在remove里面 并没有用到event的handler 不知道这里到底有什么用 且有多个事件的时候这个事件被取代
event.handler = handler;
//执行事件 并且是用元素调用的事件 可以吧事件里面的this执行元素 ret为函数的返回值
var ret = handler.apply(this, arguments);
//如果有返回值 且返回值是false 执行阻止事件冒泡 阻止执行事件默认行为
if( ret !== undefined ){
event.result = ret;
if ( ret === false ) {
event.preventDefault();
event.stopPropagation();
}
}
}
}
},
props: "altKey attrChange attrName bubbles button cancelable charCode clientX clientY ctrlKey currentTarget data detail eventPhase fromElement handler keyCode metaKey newValue originalTarget pageX pageY prevValue relatedNode relatedTarget screenX screenY shiftKey srcElement target toElement view wheelDelta which".split(" "),
fix : function(event){
//new setEvent会给event给以个expando属性 如果有中个属性 说明已经生成了event了 不需要在次对event进行包装
if ( event[expando] )
return event;
//保留一个原始的event
// new一个新的event 这个与原始的event是不同的
var originalEvent = event;
event = new setEvent( originalEvent );
//获得原始event的属性值 有哪些属性值 见 this.props
for ( var i = this.props.length, prop; i; ){
prop = this.props[ --i ];
event[ prop ] = originalEvent[ prop ];
}
//将目标元素同一成event.target
if ( !event.target )
event.target = event.srcElement || document; // Fixes #1925 where srcElement might not be defined either
//如果发现是文本节点 取他的父节点
if ( event.target.nodeType == 3 )
event.target = event.target.parentNode;
if ( !event.relatedTarget && event.fromElement )
event.relatedTarget = event.fromElement == event.target ? event.toElement : event.fromElement;
return event;
}
}
win.setEvent = function(src){
// Allow instantiation without the 'new' keyword
// Event object
if( src && src.type ){
this.originalEvent = src;
this.type = src.type;
// Event type
}else
this.type = src;
// timeStamp is buggy for some events on Firefox(#3843)
// So we won't rely on the native value
this.timeStamp = now();
// Mark it as fixed
this[expando] = true;
}
function returnFalse(){
return false;
}
function returnTrue(){
return true;
}
setEvent.prototype = {
preventDefault: function() {
var e = this.originalEvent;
if( !e )
return;
// if preventDefault exists run it on the original event
if (e.preventDefault)
e.preventDefault();
// otherwise set the returnValue property of the original event to false (IE)
e.returnValue = false;
},
stopPropagation: function() {
var e = this.originalEvent;
if( !e )
return;
// if stopPropagation exists run it on the original event
if (e.stopPropagation)
e.stopPropagation();
// otherwise set the cancelBubble property of the original event to true (IE)
e.cancelBubble = true;
},
stopImmediatePropagation:function(){
this.isImmediatePropagationStopped = returnTrue;
this.stopPropagation();
},
isImmediatePropagationStopped: returnFalse
};
})(document);
var $ = function(id){return document.getElementById(id)}
var a = function(){alert(1)}
window.onload = function(){
gevent.add($('xx'),'click',a);
gevent.add($('xx'),'click',function(){alert(1)});
gevent.add($('xx'),'click',function(){alert(2)});
gevent.add($('xx'),'click',function(){alert(3)});
gevent.add($('xx'),'click.xx',function(){alert(4)});
}
</script>
</body>
</html>
以上内容只是自己的一些理解,水平有限,难免有错,望指正...
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