1回答

• 

  aR_Easun

  2018-02-08 14:39:50

  //图片预加载_无序加载

  (function($) {

  function PreLoad(imgs, options) {

  this.imgs = (typeof imgs === 'string') ? [imgs] : imgs;

  this.opts = $.extend({}, PreLoad.DEFAULTS, options);

  if(this.opts.order === 'ordered') {

  this._ordered();

  } else {

  this._unordered();

  }

  }

  PreLoad.DEFAULTS = {

  order: 'unordered', //默认使用无序预加载

  each: null, //每张图片加载完毕后执行

  all: null, //所有图片加载完毕后执行

  };

  PreLoad.prototype._ordered = function() { //有序加载

  var opts = this.opts,

  imgs = this.imgs,

  len = imgs.lenght,

  count = 0;

  load();

  //有序预加载

  function load() {

  var imgObj = new Image();

  $(imgObj).on('load error', function() {

  opts.each && opts.each(cuont); 

  if(count >= len) {

  //所以图片已经加载完毕

  opts.all && opts.all();

  } else {

  load();

  }

  count++

  });

  imgObj.src = imgs[count];

  }

  },

  PreLoad.prototype._unordered = function() { //无序加载

  var imgs = this.imgs,

  opts = this.opts,

  count = 0,

  len = imgs.length;

  $.each(imgs, function(i, src) {

  if(typeof src != 'string') return;

  var imgObj = new Image();

  $(imgObj).on('load error', function() {

  opts.each && opts.each(count);

  if(count >= len - 1) {

  opts.all && opts.all();

  }

  count++;

  })

  imgObj.src = src;

  });

  };

  $.extend({

  preload: function(imgs, opts) {

  new PreLoad(imgs, opts);

  }

  })

  })(jQuery);

  
  

  0 0