javascript带回调函数的异步脚本载入方法实例分析

本文实例讲述了javascript带回调函数的异步脚本载入方法。分享给大家供大家参考。具体实现方法如下：

var Loader = function () { }

Loader.prototype = {

require: function (scripts, callback) {

this.loadCount = 0;

this.totalRequired = scripts.length;

this.callback = callback;

for (var i = 0; i < scripts.length; i++) {

this.writeScript(scripts[i]);

}

},

loaded: function (evt) {

this.loadCount++;

if (this.loadCount == this.totalRequired && typeof this.callback == 'function') this.callback.call();

},

writeScript: function (src) {

var self = this;

var s = document.createElement('script');

s.type = "text/javascript";

s.async = true;

s.src = src;

s.addEventListener('load', function (e) { self.loaded(e); }, false);

var head = document.getElementsByTagName('head')[0];

head.appendChild(s);

}

}

用法演示

var l = new Loader();

l.require([

"example-script-1.js",

"example-script-2.js"],

function() {

// Callback

console.log('All Scripts Loaded');

});

希望本文所述对大家的javascript程序设计有所帮助。