大侠们帮我看看 为啥火狐不支持啊这功能啊

我用的5.0版 ie下都有效果的<!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>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
div{
width:150px;
height:18px;
float:left;
font-size:14px;
}
</style>
<script language="javascript">
function yz()
{
if(user.value.length<2)
document.getElementById("yanzheng").innerHTML="用户名不能少于3个字符"
else
document.getElementById("yanzheng").innerHTML=""
setTimeout("yz()",100)
}
</script>
</head>
<body onload="yz()">
<input type="text" name="user" /><label id="yanzheng"></label>
</body>
</html>

解决方案 »

  1.   


    <!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>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>无标题文档</title>
    <style type="text/css">
    div{
    width:150px;
    height:18px;
    float:left;
    font-size:14px;
    }
    </style>
    <script language="javascript">
    function yz()
    {
    if(document.getElementByID('user').value.length<2)
    document.getElementById("yanzheng").innerHTML="用户名不能少于3个字符"
    else
    document.getElementById("yanzheng").innerHTML=""
    setTimeout("yz()",100)
    }
    </script>
    </head>
    <body onload="yz()">
    <input type="text" id="user" name="user" /><label id="yanzheng"></label>
    </body>
    </html>
      

  2.   


    <script language="javascript">
    function yz()
    {
    if(document.getElementsByName("user")[0].value.length<2)
    document.getElementById("yanzheng").innerHTML="aa"
    else
    document.getElementById("yanzheng").innerHTML=""
    setTimeout("yz()",100)
    }
    这样就可以了
      

  3.   


    <!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>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>无标题文档</title>
    <style type="text/css">
    div{
    width:150px;
    height:18px;
    float:left;
    font-size:14px;
    }
    </style>
    <script language="javascript">
    function yz()
    {
    if(document.getElementById('user').value.length<2)
    document.getElementById("yanzheng").innerHTML="用户名不能少于3个字符"
    else
    document.getElementById("yanzheng").innerHTML=""
    setTimeout("yz()",100)
    }
    </script>
    </head>
    <body onload="yz()">
    <input type="text" id="user" name="user" /><label id="yanzheng">
    </body>
    </html>