<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>欢迎来到登录界面,请登录</title>
<script type="text/javascript" src="sdda.js"></script>
<link rel="stylesheet" href="sdf.css">
</head>
<body>
<p id="meto">中国标准时间</p>
<script>document.getElementById("meto").innerHTML = Date()</script>
<div id="container" style="width: 300px" align="center">
<div id="header" style="background-color: yellow"><h2 align="center">登陆界面</h2></div>
<div id="content" style="background-color: aqua">
<p align="center">用户名:<input id="uname" type="text" name="user" placeholder="请输入账号">
</p>
<p align="center"> 密码 :<input id="upass" type="password" name="psw" placeholder="请输入密码"></p>
<br>
<div id="error_box"><br>
</div>
<input type="radio" value="stu">用户
<input type="radio" value="tea">会员
<br>
<input type="checkbox" value="true">记住密码 <a href="">登陆遇到问题</a><br>
<button onclick="fnLogin()">登陆</button>
   
<input type="button" name="regist" value="注册">
</div>
<div id="footer" style="background-color: crimson"><h3 align="center">版权@hir</h3></div>
</div>
</body>
</html>
function fnLogin() {
var oUname = document.getElementById("uname")
var oUpass = document.getElementById("upass")
var oError = document.getElementById("error_box")
if (oUname.value.length > 20 || oUname.value.length < 6) {
oError.innerHTML = "用户名为6-20位字符"
}
if (oUpass.value.length > 20 || oUpass.value.length < 6) {
oError.innerHTML = "密码为 6-20位字符"
}
}