當你只需要加載一個js文件時拍皮，可以使用這段代碼：

function loadScript(src, callback) {
    var script = document.createElement('script'),
        head = document.getElementsByTagName('head')[0];
    script.type = 'text/javascript';
    script.charset = 'UTF-8';
    script.src = src;
    if (script.addEventListener) {
        script.addEventListener('load', function () {
            callback();
        }, false);
    } else if (script.attachEvent) {
        script.attachEvent('onreadystatechange', function () {
            var target = window.event.srcElement;
            if (target.readyState == 'loaded') {
                callback();
            }
        });
    }
    head.appendChild(script);
}

//調(diào)用
loadScript('http://cdn.staticfile.org/jquery/1.6.2/jquery.min.js',function(){
    console.log('onload');
});

當你需要加載多個js文件時：

function loadScript(src, callback) {
    arraySync(function (one, i, c) {
        var cur_script = document.createElement("script");
        cur_script.type = 'text/javascript';
        cur_script.charset = 'UTF-8';
        cur_script.src = one;
        cur_script.addEventListener('load', function () {
            c(0, {
                i: i,
                v: {}
            });
        }, false);
        document.head.appendChild(cur_script)
    }, src, function (err, r) {
        //全部加載完成后執(zhí)行的回調(diào)函數(shù)
        if (err) {
            dhtmlxAlert(err.message);
        } else {
            callback()
        }
    });
}

//處理異步歹叮，不用promise的方案
function arraySync(bsFunc, ar) {
    var callback = arguments[arguments.length - 1];
    if (ar.length == 0) {
        callback(0, []);
        return;
    }
    var sendErr = false;
    var finishNum = ar.length;
    var result = [];
    var args = [0, 0];
    for (var index = 2; index < arguments.length - 1; ++index) {
        args.push(arguments[index]);
    }
    args.push(function (err, r) {
        if (err) {
            if (!sendErr) {
                sendErr = true;
                callback(err);
            }
            return;
        }
        --finishNum;
        result[r.i] = r.v;
        if (finishNum == 0) {
            callback(0, result);
        }
    });

    for (var i = 0; i < ar.length; ++i) {
        args[0] = ar[i];
        args[1] = i;
        bsFunc.apply(null, args);
    }
};

//調(diào)用
loadScript(['./jquery.min.js','./echarts.min.js','./vue.min.js'],function(){
    console.log('onload');
});

上述代碼使用了arraySync方案來處理異步，如果條件允許铆帽，你也可以使用promise來解決咆耿，效果都是一樣的。

我的項目中是需要從json文件中讀取配置爹橱，取到的數(shù)據(jù)中有需要動態(tài)加載的js列表萨螺，然后使用上述的批量加載js函數(shù)進行處理，下面給出整體代碼愧驱，有需要的可以搭配使用哦~

var loadScript = function (callback) {
    //讀取json
    var request = new XMLHttpRequest();
    request.open("get", "package.json");
    request.send(null);
    request.onload = function () {
        if (request.status == 200) {
            var package = JSON.parse(request.responseText);
            //合并dependencies和plugins對象
            Object.assign(package.dependencies, package.plugins);
            var scriptUrls = [];
            for (var i in package.dependencies) {
                scriptUrls.push(package.dependencies[i])
            }
            //異步載入script
            arraySync(function (one, i, c) {
                var cur_script = document.createElement("script");
                cur_script.type = 'text/javascript';
                cur_script.charset = 'UTF-8';
                cur_script.src = one;
                cur_script.addEventListener('load', function () {
                    c(0, {
                        i: i,
                        v: {}
                    });
                }, false);
                document.head.appendChild(cur_script)
            }, scriptUrls, function (err, r) {
                if (err) {
                    dhtmlxAlert(err.message);
                } else {
                    callback()
                }
            });
        }
    }
}

//處理異步慰技，不用promise的方案
function arraySync(bsFunc, ar) {
    var callback = arguments[arguments.length - 1];
    if (ar.length == 0) {
        callback(0, []);
        return;
    }
    var sendErr = false;
    var finishNum = ar.length;
    var result = [];
    var args = [0, 0];
    for (var index = 2; index < arguments.length - 1; ++index) {
        args.push(arguments[index]);
    }
    args.push(function (err, r) {
        if (err) {
            if (!sendErr) {
                sendErr = true;
                callback(err);
            }
            return;
        }
        --finishNum;
        result[r.i] = r.v;
        if (finishNum == 0) {
            callback(0, result);
        }
    });

    for (var i = 0; i < ar.length; ++i) {
        args[0] = ar[i];
        args[1] = i;
        bsFunc.apply(null, args);
    }
};