js 自动播放的实例代码

  

复制代码 代码如下:

  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

  <html>

  <head>

  <meta http-equiv="content-type" content="text/html; charset=utf-8" />

  <title>auto play</title>

  <script type="text/javascript" src="../jquery-1.8.0.min.js" /></script>

  <script type="text/javascript">

  //数组的第一项为时长,其他项可自定义

  data = [["3","a"],["2","b"],["3","c"],["2","d"],["1",""]];

  $(document).ready(function(){

  //设置触发事件

  autoPlay.run = function(obj,num){

  back(obj,num);

  };

  autoPlay();

  });

  function back(obj,num){

  $("#div_show").html(obj[num][1]);

  }

  function autoPlay(){

  //初始化计数参数

  if(autoPlay.num ==undefined)

  autoPlay.num = 0;

  //初始化时间点

  if(autoPlay.timepoint ==undefined)

  autoPlay.timepoint = new Date().getTime();

  if(autoPlay.num<data.length){

  //函数句柄,data 数组,autoPlay.num当前下标

  autoPlay.run(data,autoPlay.num);

  //按照元素时间长度播放数组

  if(new Date().getTime()>autoPlay.timepoint){

  //判断是否为第一次执行

  if(autoPlay.first==undefined)

  autoPlay.first = true;

  else

  autoPlay.num++;

  //设置下一次播放的时间点

  autoPlay.timepoint += (data[autoPlay.num][0]*1000);

  }

  setTimeout("autoPlay()",500);

  }

  }

  $.extend({autoPlay:function(){

  var defaults = {inteval:500};

  }});

  </script>

  </head>

  <body>

  <div id="div_show"></div>

  </body>

  </html>

  定义播放时间,可以定义事件