IE在DOM操作有表单控件时的bug

bug描述
当象下例中那样操作了表单radio/checkbox的DOM结构时（或者直接影响了他们的结构时）选中的checkbox/radio将会自动恢复到默认状态，有如点了reset按钮一样。

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" 
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Rank's HTML document</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<meta http-equiv="Pragma" content="no-cache" /> 
<meta http-equiv="Cache-Control" content="no-cache" /> 
<meta http-equiv="Expires" content="0" />
<meta http-equiv="ImageToolbar" content="no" />
<meta http-equiv="Creator.name" content="Rank, BlueDestiny, never-online" />
<style type="text/css" title="default" media="screen">
/*<![CDATA[*/
body { font-size:80%; line-height:1.5; }
body, button { font-family:arial; }
button { padding:0 0.3em 0 0.3em; }
h1, h3 { margin:0; padding:0; }
h1 { font-size:2.3em; }
h3 { font-size:1.3em; }
form { display:inline-block; }
div.link { padding:1em; }
div.content { background:#ffc; padding:1em; border:1px solid #222; margin:1em 0 1em; }
#rdoWrapper { }
#hd { text-align:center; }
/*]]>*/
</style>
</head>
<body>
<div id="hd">
<h2> IE form control bug </h2>
<div class="link">from: <em>never-online weblog</em></div>
</div>
<div id="rdoWrapper" class="content">
<h3> 1. Select radio to checked </h3>

</div>
<div class="content">
<h3> 2. Click button to change dom structure </h3>
<p class="p"><button type="button" onclick="handleChangeDom()">test</button></p>
</div>
<script type="text/javascript">//<![CDATA[
function getRadioValue(ctlName) {
var ctls = document.getElementsByName(ctlName);
var len = ctls.length;
for (var i=0; i<len; i++) {
if (ctls[i].checked) {
return ctls[i].value;
}
}
}
function handleChangeDom() {
alert('before append, you select radio value is "'+getRadioValue('rdo')+'"');
var wrapper = document.getElementById('rdoWrapper');
document.body.appendChild(wrapper);
alert('after append, you select radio value is "'+getRadioValue('rdo')+'"');
}
//]]></ script>
</body>
</html>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]

解决方法
可以在操作DOM之前，用defaultChecked来设置checked的值。

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" 
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Rank's HTML document</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<meta http-equiv="Pragma" content="no-cache" /> 
<meta http-equiv="Cache-Control" content="no-cache" /> 
<meta http-equiv="Expires" content="0" />
<meta http-equiv="ImageToolbar" content="no" />
<meta http-equiv="Creator.name" content="Rank, BlueDestiny, never-online" />
<style type="text/css" title="default" media="screen">
/*<![CDATA[*/
body { font-size:80%; line-height:1.5; }
body, button { font-family:arial; }
button { padding:0 0.3em 0 0.3em; }
h1, h3 { margin:0; padding:0; }
h1 { font-size:2.3em; }
h3 { font-size:1.3em; }
form { display:inline-block; }
div.link { padding:1em; }
div.content { background:#ffc; padding:1em; border:1px solid #222; margin:1em 0 1em; }
#rdoWrapper { }
#hd { text-align:center; }
/*]]>*/
</style>
</head>
<body>
<div id="hd">
<h2> fixed IE form control bug </h2>
<div class="link">from: <em>never-online weblog</em></div>
</div>
<div id="rdoWrapper" class="content">
<h3> 1. Select radio to checked </h3>

</div>
<div class="content">
<h3> 2. Click button to change dom structure </h3>
<p class="p"><button type="button" onclick="handleChangeDom()">test</button></p>
</div>
<script type="text/javascript">//<![CDATA[
function getRadioValue(ctlName) {
var ctls = document.getElementsByName(ctlName);
var len = ctls.length;
for (var i=0; i<len; i++) {
if (ctls[i].checked) {
return ctls[i].value;
}
}
}
function setRadioDefaultValue(ctlName) {
var ctls = document.getElementsByName(ctlName);
var len = ctls.length;
for (var i=0; i<len; i++) {
ctls[i].defaultChecked = ctls[i].checked;
}
}
function handleChangeDom() {
alert('before append, you select radio value is "'+getRadioValue('rdo')+'"');
setRadioDefaultValue('rdo');
var wrapper = document.getElementById('rdoWrapper');
document.body.appendChild(wrapper);
alert('after append, you select radio value is "'+getRadioValue('rdo')+'"');
}
//]]></ script>
</body>
</html>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]

IE在DOM操作有表单控件时的bug_表单特效