<div class="slider"><!-- 特效區(qū) -->
  <div class="main"><!-- 主視圖區(qū) -->
    <div class="main_i">
      <div class="caption">
        <h2>h2 caption</h2>
        <h2>h3 caption</h2>
      </div>
    <img src="images/{{index}}.jpg" alt="">
    </div>
  </div><!-- 主視圖區(qū)結(jié)束 -->
  <div class="ctrl"><!-- 控制區(qū) -->
    <a href="javascript:;"><img src="images/{{index}}.jpg" alt="">
    </a>
  </div><!-- 控制區(qū)結(jié)束 -->
</div><!-- 特效區(qū)結(jié)束 -->

<script type="text/javascript">

  // 1、數(shù)據(jù)定義（實(shí)際生產(chǎn)環(huán)境，應(yīng)由后臺(tái)給出）
  var data = [
    {img:1,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:2,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:3,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:4,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:5,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:6,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
    {img:7,h2:"我是標(biāo)題二,小標(biāo)題",h3:"我是標(biāo)題三,大標(biāo)題"},
  ];

  // 2、通用函數(shù)
  var g = function(id){
    if( id.substr(0,1) =="." ){
      return document.getElementsByClassName( id.substr(1) );
    }
    return document.getElementById(id);
  }

  // 3、添加幻燈片的操作（所有幻燈片&對(duì)應(yīng)的按鈕）
  function addSliders(){
    // 3.1 獲取模版
    var tpl_main = g("template_main").innerHTML
      .replace(/^\s*/,'')
      .replace(/\s*$/,'');

    var tpl_ctrl = g("template_ctrl").innerHTML
      .replace(/^\s*/,'')
      .replace(/\s*$/,'');

    // 3.2 定義最終輸出HTML的變量
    var out_main = [];
    var out_ctrl = [];

    // 3.3 遍歷所有數(shù)據(jù)，構(gòu)建最終輸出的HTML
    for( i in data ){
      var _html_main = tpl_main
        .replace(/{{index}}/g,data[i].img)
        .replace(/{{h2}}/g,data[i].h2)
        .replace(/{{h3}}/g,data[i].h3)
        .replace(/{{css}}/g,['','main_i_right'][i%2]);

      var _html_ctrl = tpl_ctrl
        .replace(/{{index}}/g,data[i].img);
      
      out_main.push(_html_main);
      out_ctrl.push(_html_ctrl);
    }

    // 3.4 把HTML回寫到對(duì)應(yīng)的DOM里面
    g("template_main").innerHTML = out_main.join('');
    g("template_ctrl").innerHTML = out_ctrl.join('');
    
    // 7、增加#main_background
    g('template_main').innerHTML += tpl_main
      .replace(/{{index}}/g,'{{index}}')
      .replace(/{{h2}}/g,data[i].h2)
      .replace(/{{h3}}/g,data[i].h3);

    g('main_{{index}}').id = 'main_background';
  }

  // 5、幻燈片切換
  function switchSliders(n){
    // 5.1 獲得要展現(xiàn)的幻燈片&控制按鈕 DOM
    var main = g("main_"+n);
    var ctrl = g("ctrl_"+n);

    // 5.2 獲得所有的幻燈片&控制按鈕
    var clear_main = g('.main_i');
    var clear_ctrl = g('.ctrl_i');

    // 5.3 清除他們的active樣式
    for(var i=0;i<clear_ctrl.length;i++){
      clear_main[i].className = clear_main[i].className.replace('main_i_active','');
      clear_ctrl[i].className = clear_ctrl[i].className.replace('ctrl_i_active','');
    }

    // 5.4為當(dāng)前控制按鈕和幻燈片附加樣式  
    g("main_"+n).className += ' main_i_active';
    g("ctrl_"+n).className += ' ctrl_i_active';
    // 7.2切換時(shí) 復(fù)制上一張幻燈片到main_background中
    setTimeout(function(){
      g('main_background').innerHTML = main.innerHTML;
    },1000);
    
  }

  // 6、動(dòng)態(tài)調(diào)整圖片的margin-top 使其垂直居中
  function movePictures(){
    var pictures = g('.picture');
    for(i=0;i<pictures.length;i++){
      pictures[i].style.marginTop = -(pictures[i].clientHeight/3) + 'px';
    }
  }

  // 4、定義何時(shí)處理幻燈片輸出
  window.onload = function(){
    addSliders();
    switchSliders(1);
    setTimeout(function(){
      movePictures();
    },100)
  }
</script>