requirejs

[hytzgroup]

(function(global){
    var defineModels = {};
    function load(url,callback){
        var $body = document.body || document.getElementsByTagName('body')[0];
        var $script = document.createElement('script');
        $script.async = true;
        $script.src = './'+url+'.js';
        $script.onload = function(event){
            callback(event);
        }
        $body.appendChild($script);
    }

    function req(deps,callback){
        if(!deps.length){
            callback();
        }
        var params = [];
        var total = deps.length;
        for(var i = 0, len = deps.length; i < len; i++){
            (function(index,params){
                load(deps[index],function(event){
                    --total;
                    var id = deps[index];
                    defineModels[id].loaded = true;
                    params.push(defineModels[id].callback());
                    if(total == 0){
                        callback.apply(null,params);
                    }
                });
            })(i,params);
        }
    }

    function define(id,callback){
        defineModels[id] = {
            loaded:false,
            callback:callback,
            params:null
        }
    }

    global.require = req;
    global.define = define;

})(window);

[hytzgroup]

(function(global){
    var defineModels = {};
    function loadScript(url,callback){
        var $body = document.body || document.getElementsByTagName('body')[0];
        var $script = document.createElement('script');
        $script.async = true;
        $script.src = './'+url+'.js';
        $script.onload = function(event){
            callback(event);
        }
        $body.appendChild($script);
    }
    function load(id,callback){
        loadScript(id,function scriptFn(){
            // b model
            var model = getModel(id);
            // load b model deps e
            req(model.deps,function reqFn2(param){
                callback(model.callback(param));
            });
        });
    }
    function getModel(id){
        return defineModels[id];
    }
    // 职责链模式递归循环
    function req(deps,callback){
        var params = [];
        if(!deps.length){
            return callback();
        }
        var total = deps.length;
        for(var i = 0, len = deps.length; i < len; i++){
            (function(index){
                // load b.js
                load(deps[index],function loadFn(param){
                    --total;
                    params.push(param);
                    if(total == 0){
                        callback.apply(null,params);
                    }
                });
            })(i);
        }
    }
    // 模块
    function define(id,deps,callback){
        defineModels[id] = {
            loaded:false,
            deps:deps,
            callback:callback
        }
    }

    global.require = req;
    global.define = define;

})(window);

[hytzgroup]

req(['b'],reqFn)

load('b',function loadFn(){

    callback = reqFn;
})

loadScript('b',function scriptFn(){
    // 成功加载 model b
    req(['e'],function reqFn2(){
        callback = loadFn;
    });
});

load('e',function loadFn(){
    callback = reqFn2;
});

loadScript('b',function scriptFn(){
    // 成功加载 model e
    req([],function reqFn2(){
        callback = loadFn;
    });
});

reqFn2();