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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title> new document </title>
    <meta name="generator" content="editplus" />
    <meta name="author" content="Gao YiXiang" />
    <meta name="email" content="[email protected]" />
    <meta name="keywords" content="javascript dhtml dom" />
    <meta name="description" content="I love web development." />
</head>
<body>
    <div id="divP" class="">
        <input type="text" id="i1" />
        <select id="i2">
            <option id="i201" value="" selected="selected"></option>
            <option id="i202" value=""></option>
        </select>
        heiheihahei
        <textarea id="i3" rows="" cols=""></textarea>
    </div>
    <script type="text/javascript">
    <!--
var i1 = document.getElementById("i1");
var c = i1.parentNode.childNodes;
for (var p in c)
{
    if (c[p].nodeType == 1)
    {
        alert(c[p].id);
    }
}
    //-->
    </script>
</body>
</html>
送你三本手册!DHTML参考手册
http://download.csdn.net/source/308913样式表中文手册
http://download.csdn.net/source/304124JScript语言参考
http://download.csdn.net/source/308916