data.js

//==================================================
// 数据缓存模块
//==================================================
define("data", ["$lang"], function(){
    $.log("已加载data模块",7);
    var remitter = /object|function/, rtype = /[^38]/
    function validate(target){
        return target && remitter.test(typeof target) && rtype.test(target.nodeType)
    }
    $.mix( {
        "@data": {},
        // 读写数据
        data : function( target, name, data, pvt ) {//IE678不能为文本节点注释节点添加数据
            if( validate(target) ){
                var id = $.getUid(target), isEl = target.nodeType === 1;
                if(name === "@uuid"){
                    return id;
                }
                var getByName = typeof name === "string",
                database = isEl ? $["@data"]: target,
                table = database[ "@data_"+id ] || (database[ "@data_"+id ] = {
                    data:{}
                });
                var inner = table;
                //对于用HTML5 data-*属性保存的数据， 如<input id="test" data-full-name="Planet Earth"/>
                //我们可能通过$("#test").data("full-name")或$("#test").data("fullName")访问到
                if(isEl && !table.parsedAttrs){
                    var attrs = target.attributes;
                    //将HTML5单一的字符串数据转化为mass多元化的数据，并储存起来
                    for ( var i = 0, attr; attr = attrs[i++];) {
                        var key = attr.name;
                        if ( key.indexOf( "data-" ) === 0 && key.length > 5 ) {
                            $.parseData(target, key.slice(5), inner, attr.value);
                        }//camelize
                    }
                    table.parsedAttrs = true;
                }
                //私有数据都是直接放到table中，普通数据放到table.data中
                if ( !pvt ) {
                    table = table.data;
                }
                if ( name && typeof name == "object" ) {
                    $.mix( table, name );//写入一组方法
                }else if(getByName && data !== void 0){
                    table[ name ] = data;//写入单个方法
                }
                if(getByName){
                    if(name in table){
                        return table[name]
                    }else if(isEl && !pvt){
                        return $.parseData( target, name, inner );
                    }
                }else{
                    return table
                }
            }
            return  void 0
        },//仅内部调用
        _data:function(target,name,data){
            return $.data(target, name, data, true)
        },
        parseData: function(target, name, table, value){
            var data, key = $.String.camelize(name);
            if(table && (key in table))
                return table[key];
            if(arguments.length != 4){
                var attr = "data-" + name.replace( /([A-Z])/g, "-$1" ).toLowerCase();
                value = target.getAttribute( attr );
            }
            if ( typeof value === "string") {//转换
                try {
                    data = eval("0,"+ value );
                } catch( e ) {
                    data = value
                }
                if(table){
                    table[ key ] = data
                }
            }
            return data;

        },
        //移除数据
        removeData : function(target, name, pvt){
            if( validate(target) ){
                var id =  $.getUid(target);
                if (  !id ) {
                    return;
                }
                var  clear = 1, ret = typeof name == "string",
                database = target.nodeType === 1  ? $["@data"] : target,
                table = database["@data_"+id] ;
                if ( table && ret ) {
                    if(!pvt){
                        table = table.data
                    }
                    if(table){
                        ret = table[ name ];
                        delete table[ name ];
                    }
                    var cache = database["@data_"+id];
                        loop:
                        for(var key in cache){
                            if(key == "data"){
                                for(var i in cache.data){
                                    clear = 0;
                                    break loop;
                                }
                            }else{
                                clear = 0;
                                break loop;
                            }
                        }
                }
                if(clear){
                    try{
                        delete database["@data_"+id];
                    }catch(e){
                        database["@data_"+id] = void 0;
                    }
                }
                return ret;
            }
        },
        //合并数据
        mergeData: function( cur, src){
            var oldData  = $._data(src), curData  = $._data(cur), events = oldData .events;
            if(oldData  && curData ){
                $.Object.merge( curData , oldData  );
                if(events){
                    curData .events = [];
                    for (var i = 0, item ; item =  events[i++]; ) {
                        $.event.bind.call( cur, item );
                    }
                }
            }
        }
    });
});

/**
2011.9.27 uniqueID改为uniqueNumber 简化data与removeData
2011.9.28 添加$._data处理内部数据
2011.10.21 强化mergeData，可以拷贝事件
2012.1.31 简化$.Object.merge的调用
2012.4.5 修正mergeData BUG, 让$.data能获取HTML5 data-*
2012.5.2 $._db -> $["@data]
2012.5.21 抽象出validate私有方法
*/