var rbrace = /(?:\{[\s\S]*\}|\[[\s\S]*\])$/,rmultiDash= /([A-Z])/g;function internalData( elem, name, data, pvt /*Internal Use Only*/){//如果elem元素不能附加值，退出if ( !jQuery.acceptData( elem ) ) {return;}//## form core.js//Unique for each copy of jQuery on the page//Non-digits removed to match rinlinejQuery//expando: "jQuery" + ( core_version + Math.random() ).replace( /\D/g, "" ),//每个Jquery都有单独的一个expandovarret, thisCache,internalKey=jQuery.expando,//We have to handle DOM nodes and JS objects differently because IE6-7//can't GC object references properly across the DOM-JS boundary//由于IE6,7不能自动回收再DOM上的引用，所以要对DOM和JS对象区别对待isNode =elem.nodeType,//Only DOM nodes need the global jQuery cache; JS object data is//attached directly to the object so GC can occur automatically//只有DOM需要全局的缓存变量，对象就直接插入值了cache = isNode ?jQuery.cache : elem,//Only defining an ID for JS objects if its cache already exists allows//the code to shortcut on the same path as a DOM node with no cacheid = isNode ? elem[ internalKey ] : elem[ internalKey ] &&internalKey;//什么时候会出现id为undefined的时候？//internalData(document.createElement('div'),'namea',...)//internalData({});//Avoid doing any more work than we need to when trying to get data on an//object that has no data at allif ( (!id || !cache[id] || (!pvt && !cache[id].data)) && data === undefined && typeof name === "string") {return;}//如果有name而没有data，说明这是一个读取的动作//但是没有得到id，获取cache[id]中啥都没有，在获取用户数据的时候cache[id].data啥都木有，就返回空if ( !id ) {//Only DOM nodes need a new unique ID for each element since their data//ends up in the global cache//如果是DOM元素，则取得一个唯一的ID值if( isNode ) {id= elem[ internalKey ] = core_deletedIds.pop() || jQuery.guid++; }else{id= internalKey; //这是jQuery.expando
}}if ( !cache[ id ] ) {//Avoid exposing jQuery metadata on plain JS objects when the object//is serialized using JSON.stringify//避免只用JSON.stringify(cache[id]) 所带来的循环引用cache[ id ] = isNode ?{} : { toJSON: jQuery.noop };}//An object can be passed to jQuery.data instead of a key/value pair; this gets//shallow copied over onto the existing cache//也可以穿一个jQuery.data，浅拷贝过来//jQuery.data({},{name:'hhstuhacker',age:31})//cache[id] = {data:{name:'hhstuhacker',age:31}};//cache[ id ]存入的是jQuery的内部数据//cache[ id ].data 存入的是用户数据//若果pvt为真，就拷贝到cache[ id ]里//若果pvt为false，就拷贝到cache[ id ].data 里if ( typeof name === "object" || typeof name === "function") {if( pvt ) {cache[ id ]= jQuery.extend( cache[ id ], name ); //直接拷贝，内部使用} else{cache[ id ].data= jQuery.extend( cache[ id ].data, name ); //直接拷贝data
}}thisCache=cache[ id ];//jQuery data() is stored in a separate object inside the object's internal data//cache in order to avoid key collisions between internal data and user-defined//data.//jQuery.cache = {jQuery.expando: {data:{}}};//这里是为了防止内部数据跟用户定义的数据项混淆，内部数据定义在jQ.cache里，用户定义数据在jQ.cache.[id] 里if ( !pvt ) {if ( !thisCache.data ) {thisCache.data={};}thisCache=thisCache.data;}//分情况了，如果传入了键值对，就设置之//将camelCase驼峰if ( data !==undefined ) {thisCache[ jQuery.camelCase( name ) ]=data;}//Check for both converted-to-camel and non-converted data property names//If a data property was specified//不管是否读取还是设置缓存，都会返回数据//先尝试直接获取，如果获取不成功，就尝试驼峰式获取//如果连name都没有指定，就获取整个thisCache对象if ( typeof name === "string") {//First Try to find as-is property dataret =thisCache[ name ];//Test for null|undefined property dataif ( ret == null) {//Try to find the camelCased propertyret =thisCache[ jQuery.camelCase( name ) ];}}else{ret=thisCache;}returnret;
}functioninternalRemoveData( elem, name, pvt ) {if ( !jQuery.acceptData( elem ) ) { //如果elem元素不能附加值，退出return; }varthisCache, i,isNode=elem.nodeType,//See jQuery.data for more informationcache = isNode ?jQuery.cache : elem,id= isNode ?elem[ jQuery.expando ] : jQuery.expando;//If there is already no cache entry for this object, there is no//purpose in continuing//如果没有得到cache[ id ] 那就不进行了if ( !cache[ id ] ) {return;}if( name ) {thisCache= pvt ?cache[ id ] : cache[ id ].data;if( thisCache ) {//Support array or space separated string names for data keys//$.removeData(element,['title','age','createTime']);//$.removeData(element,'title age createTime');if ( !jQuery.isArray( name ) ) {//try the string as a key before any manipulationif ( name inthisCache ) {name=[ name ];}else{//split the camel cased version by spaces unless a key with the spaces exists//检测是否驼峰式在其中，如果不在，将其splitname =jQuery.camelCase( name );if ( name inthisCache ) {name=[ name ];}else{name= name.split(" ");}}}else{//If "name" is an array of keys...//When data is initially created, via ("key", "val") signature,//keys will be converted to camelCase.//Since there is no way to tell _how_ a key was added, remove//both plain key and camelCase key. #12786//This will only penalize the array argument path.name =name.concat( jQuery.map( name, jQuery.camelCase ) );//将不驼峰和驼峰的全部删除
}//删除之i =name.length;while ( i--) {deletethisCache[ name[i] ];}//If there is no data left in the cache, we want to continue//and let the cache object itself get destroyed//如果说删除过后，cache[id]或者cache[id].data 都是空了，那么咱们需要清理下一步吧？if ( pvt ? !isEmptyDataObject(thisCache) : !jQuery.isEmptyObject(thisCache) ) {return;}}}//See jQuery.data for more information//如果是用户使用的话，清空cache[id].data//如果cache [ id ] 不是空的话，结束该函数//如果cahce [ id ] 是空的话，还是下一步的清理行动啊if ( !pvt ) {deletecache[ id ].data;//Don't destroy the parent cache unless the internal data object//had been the only thing left in itif ( !isEmptyDataObject( cache[ id ] ) ) {return;}}//window.window === window;//isWindow: function (o) {return o.window === window;}//cache != cache.window 表示不是window//Destroy the cache//如果是个DOM节点，那么cleanDataif( isNode ) {jQuery.cleanData( [ elem ],true);//ses: http://www.cnblogs.com/enein/archive/2012/08/23/2651312.html//Use delete when supported for expandos or `cache` is not a window per isWindow (#10080)//经测试，在IE6,7,8下面，var div = document.createElement('div') delete div.test;//是报错的 而 jQuery.support.deleteExpando 正是这种检测} else if ( jQuery.support.deleteExpando || cache !=cache.window ) {deletecache[ id ];//When all else fails, null} else{cache[ id ]= null;}
}jQuery.extend({cache: {},//The following elements throw uncatchable exceptions if you//attempt to add expando properties to them.//这几个元素不能有附加值
noData: {"applet": true,"embed": true,//Ban all objects except for Flash (which handle expandos)"object": "clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"},hasData:function( elem ) {elem= elem.nodeType ?jQuery.cache[ elem[jQuery.expando] ] : elem[ jQuery.expando ];return !!elem && !isEmptyDataObject( elem );},data:function( elem, name, data ) {returninternalData( elem, name, data );},removeData:function( elem, name ) {returninternalRemoveData( elem, name );},//For internal use only.//内部适用，这里设置pvt为true，返回内部数据，定位到cache[id]这一层_data: function( elem, name, data ) {return internalData( elem, name, data, true);},//内部适用，这里设置pvt为true，返回内部数据，定位到cache[id]这一层_removeData: function( elem, name ) {return internalRemoveData( elem, name, true);},//A method for determining if a DOM node can handle the data expandoacceptData: function( elem ) {//Do not set data on non-element because it will not be cleared (#8335).//如果是个dom节点，并且不是element也不是document，那就表示不能被附加数据//see:http://www.cnblogs.com/hhstuhacker/p/NodeType.htmlif ( elem.nodeType && elem.nodeType !== 1 && elem.nodeType !== 9) {return false;}var noData = elem.nodeName &&jQuery.noData[ elem.nodeName.toLowerCase() ];//nodes accept data unless otherwise specified; rejection can be conditional//如果是embed或者applet，或者是flash元素，就返回false//about falsh:: http://www.w3help.org/zh-cn/causes/HO8001return !noData || noData !== true && elem.getAttribute("classid") ===noData;}
});jQuery.fn.extend({data:function( key, value ) {varattrs, name,data= null,i= 0,elem= this[0];//Special expections of .data basically thwart jQuery.access,//so implement the relevant behavior ourselves//Gets all values//如果key为undefined，那就表示要取得所有的dataif ( key ===undefined ) {if ( this.length ) { data= jQuery.data( elem ); //默认取第一个//看看cache内部是否已经解析过该DOM了，parsedAttrs//如果没有，得到属性列表if ( elem.nodeType === 1 && !jQuery._data( elem, "parsedAttrs") ) {attrs=elem.attributes;for ( ; i < attrs.length; i++) {name=attrs[i].name;if ( name.indexOf("data-") === 0) {name= jQuery.camelCase( name.slice(5) );//这里的data[ name ]为空值
dataAttr( elem, name, data[ name ] );}}//标记已经解析过了jQuery._data( elem, "parsedAttrs", true);}}returndata;}//Sets multiple values//如果是个对象，递归调用之if ( typeof key === "object") {return this.each(function() {jQuery.data(this, key );});}return arguments.length > 1 ?//Sets one valuethis.each(function() {jQuery.data(this, key, value );}) ://$('.color-box').data('someone','new');//Gets one value//Try to fetch any internally stored data firstelem ? dataAttr( elem, key, jQuery.data( elem, key ) ) : null;//$('#box').data('dataFirst');//<div data-data-first="something....."></div>
},removeData:function( key ) {return this.each(function() {jQuery.removeData(this, key );});}
});functiondataAttr( elem, key, data ) {//If nothing was found internally, try to fetch any//data from the HTML5 data-* attribute//这个函数，主要是处理HTML5的问题if ( data === undefined && elem.nodeType === 1) {//驼峰反转var name = "data-" + key.replace( rmultiDash, "-$1").toLowerCase();data=elem.getAttribute( name );//rbrace 对象或者数组正则if ( typeof data === "string") {try{data= data === "true" ? true:data=== "false" ? false:data=== "null" ? null://Only convert to a number if it doesn't change the string+data + "" === data ? +data :rbrace.test( data )?jQuery.parseJSON( data ) :data;}catch( e ) {}//Make sure we set the data so it isn't changed later
jQuery.data( elem, key, data );//设置进去
}else{data=undefined;}}returndata;
}//checks a cache object for emptiness
functionisEmptyDataObject( obj ) {varname;for ( name inobj ) {//if the public data object is empty, the private is still empty//如果cache.data 为空，跳过本次循环，不判断了//如果不跳过啊，就走到下面了吧，name !== data 杠杠的if ( name === "data" &&jQuery.isEmptyObject( obj[name] ) ) {continue;}//toJSON是内置的，如果看到其他name，就不为空if ( name !== "toJSON") {return false;}}return true;
}

jQuery的版本为1.9.2