类数组对象HTMLCollenction

提示：扫一扫查出行
【扫一扫了解最新限行尾号】
复制提示

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <script src="js/domready.js"></script>
    <script>
        myReady(function(){
            //以下是HTMLCollection类数组对象//
            //var scripts=document.scripts;
            //console.log(scripts);//返回：HTMLCollection(2) [script, script]
            //var links=document.links;
            //console.log(links);//返回：HTMLCollection(10) [a, a#onea, a, a, a, a, a, a, a, a, onea: a#onea]
            //var images=document.images;
            //console.log(images);//返回：HTMLCollection(2) [img, img]
            //var forms=document.forms;
            //console.log(forms);//返回：HTMLCollection(2) [form, form]
            //var cells=document.getElementById("tr").cells;
            //console.log(cells);//返回：HTMLCollection(3) [td, td, td](火狐)
            //var options=document.getElementById("city").options;
            //console.log(options);//返回：HTMLOptionsCollection(5) [option, option, option, option, option, selectedIndex: 0]
            //var ps=document.getElementsByTagName("p");
            //console.log(ps);//返回：HTMLCollection(3) [p, p, p]

            //var cells=document.getElementById("tr").cells;
            //console.log(cells);//返回HTMLCollection类数组对象：HTMLCollection(3) [td#td, td, td, td: td#td]（谷歌）
            //console.log(cells.length);
            //console.log(cells.item(2));
            //console.log(cells.item(3));//超过类数组对象的长度时，显示为null
            //console.log(cells.namedItem("td"));//返回 cells 类数组中先查找 id="td"的cell对象，如不存在，则查找name="td"的cell对象，如果存在多个name="td"，则返回第一个。如果两个都不存在，则返回null对象。
            //=================以上是HTMLCollection类数组对象======================

//=================以下是NamedNodeMap类数组对象======================
            var box=document.getElementById("tab");//获取table对象
            var attributes=box.attributes;//获得box对象的属性。
            //console.log(attributes);
            //console.log(attributes.length);
            //console.log(attributes.style);
            //console.log(attributes.item(0));
            //console.log(attributes.item(1));
            //console.log(attributes.getNamedItem("style"));//获取指定属性的值。
            //console.log(attributes.removeNamedItem("style"));//删除指定属性,页面内的样式就会消失


            //=================HTMLCollection类数组对象创建节点实例======================
            var ps=document.getElementsByTagName("p");//获得HTMLCollection类数组对象
            var length=ps.length;
            alert(length);
            var i=0;
            while (i<length) {//这里不能写i=ps.length，(死循环),因为HTMLCollection类数组对象活的，每当文档结构发生变化时，都会进行更新。HTMLCollection,NamedNodeMap,NodeList
              var a=document.createElement("p");
              var txt=document.createTextNode("<h1>you are my sumshime"+i);
              a.appendChild(txt);
             document.getElementById("div").appendChild(a);
             i++;
            }

        })
    </script>
</head>
<body id="body">
    <div id="div">
        <ul id="ul1">
            <li id="oneLi"><a href="">1111</a><a href="" id="onea">22222</a><span id="span1"> </span> <span id="span2"></span></li>
            <li id="twoLi" name="oneLi"><a href="">4444</a><a href="" >5555</a><a href="">6666</a></li>
            <li id="threeLi"><a href="">7777</a><a href="" >8888</a><a href="">9999</a></li>
        </ul>
        <table id="tab" style="border: 1px solid #333; display:block;">
          <tr id="tr1" name="tr1">
            <td id="td">table</td>
            <td name="td">table1</td>
            <td name="td">table2</td>
          </tr>
          <tr id="tr2">
            <td>table</td>
            <td>table</td>
            <td>table</td>
          </tr>
        </table>
        <img src="" alt="" style="display: block; border: 1px solid; width: 100px; height: 100px; "><img src="" alt="" style="display: block; border: 1px solid; width: 100px; height: 100px; ">
        <form action="">
          姓名：<input type="text" name="name" value="张三">
          <input type="button" name="submit" value="提交">
        </form>
        <form action="">
          地址：<input type="text" name="address" value="中国">
          <input type="button" name="submit" value="提交">
        </form>
        <a href=""></a><a href=""></a>
        <select name="city" id="city">
          <option value="0">北京</option>
          <option value="1">上海</option>
          <option value="2">深圳</option>
          <option value="3">重庆</option>
          <option value="4">厦门</option>
        </select>
        <p>基础挤出机会</p>
        <p>基础挤出机会</p>
        <p>基础挤出机会</p>
    </div>
</body>