<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>jsDemo</title>
</head>
<body>
<p id="demo">ppp</p>
<script>
document.write(Date()).innerHTML=123;
document.getElementById("demo").innerHTML=Date();
</script>
<button type="button" onclick=window.alert("number")>press</button>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>登录</title>
<link href="../static/css/long.css" rel="stylesheet" type="text/css">
<script>
function fnLogin(){
var oUname = document.getElementById("uname")
var oError=document.getElementById("error_box")
var oUpass = document.getElementById("upass")
if(oUname.value.length==0){
oError.innerHTML="请输入用户名"
}
if(oUname.value.length<6){
oError.innerHTML="用户名至少6位"
}
if(oUname.value.length>12){
oError.innerHTML="用户名至多12位"
}
if(oUpass.value.length==0){
oError.innerHTML="请输入密码"
}
if(oUpass.value.length<6){
oError.innerHTML="密码至少6位"
}
if(oUpass.value.length>20){
oError.innerHTML="密码至多20位"
}
}
</script>
</head>
<body style="background-color:yellow">
<div class="box">
<h2 class="denglu">登录</h2>
<div class="input_box">
<input id="uname" type="text" placeholder="请输入用户名">
</div>
<div class="input_box">
<input id="upass" type="password" placeholder="请输入密码">
</div>
<div id="error_box"><br></div>
<div class="input_box">
<button onclick="fnLogin()">登录</button>
</div>
</div>
</body>
</html>
.box{
border:1px solid#cccccc;
width:334px;
margin:5px;
text-align:center;
}
.denglu{
background-color:pink;
font-family:华文；
font-size:40px;
}
.input_box{
height:45px;
}
