An example of an asynchronous script loading method with a callback function in JavaScript _javascript tips

This example describes the asynchronous script loading method for JavaScript with callback functions. Share to everyone for your reference. The implementation methods are as follows:

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 ();
  },< C16/>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);
  }

Usage Demo

var L = new Loader ();
L.require ([
  "Example-script-1.js",
  "Example-script-2.js"],
  function () {
    //Callback
    Console.log (' All Scripts Loaded ');
  };

I hope this article will help you with your JavaScript programming.