<html>
<head>
<title>I am a title,3q</title>
<script language="javascript">
alert(document.getElementsByTagName("title")[0].innerText);
</script>
</head>
<body>
</body>
</html>
<html>
<head>
<title>I am a title,3q</title>
<script language="javascript">
alert(document.getElementsByTagName("title")[0].innerText);
</script>
</head>
<body>
</body>
</html>
是这样的
<img alt='key' title='key' />key
<a href=# alt='key' title='key'>key</a>
要取的是最后一个key 而不是alt和title的属性
<html>
<head>
<title>I am a title,3q</title>
<script language="javascript">
function repa(tagName)
{
alert(document.getElementsByTagName(tagName)[0].innerText);
} </script>
</head>
<body onload="repa('a')">
<a href="#" title="key">keyContent2</a>
</body>
</html>
html的内容是不固定的 无法确定tagName和具体位置 有可能嵌套很多 标签也不一定
div a img p b 等等都有
title：中华人民共和国<img src='http://webim.csdn.net/UserOnlineFace/Theme1/fengzi1220.ashx' title="csdn_head" />asfasfdasfdastitleasfdsafasd<img src='http://webim.csdn.net/UserOnlineFace/Theme1/fengzi1220.ashx' title="csdn_head" />title:safsafaas
</div>
<script>
var root=document.getElementById('root');
root.innerHTML=repa('title','<span style="color:red">title</span>',root.innerHTML);
alert(root.innerHTML);
function repa(key,new_key,con){
var reg= new RegExp(key+'(?![^<]+>)','gi');
return con.replace(reg,new_key);
}
</script>