标签：
1、概述
2、String对象
样例：
<!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>表单验证</title>
<style type="text/css">
.right{ text-align:right;}
</style>
<script type="text/javascript">
function check () {
var email = document.getElementById("email").value;
if (email == "") {
alert("Email不能为空");
return false;
}
if (email.indexOf("@")== -1 || email.indexOf(".")== -1) {
alert("Email格式不正确。");
return false;
}
var pwd = document.getElementById("pwd").value;
if (pwd == ""){
alert("密码不能为空。");
return false;
}
if (pwd.length < 6) {
alert("密码长度不能小于6位。");
return false;
}
var repwd = document.getElementById("repwd").value;
if (repwd != pwd) {
alert("两次输入密码不一致。");
return false;
}
var user = document.getElementById("user").value;
if (user == "") {
alert("姓名不能为空。");
return false;
}
for (var i = 0 ; i < user.length ; i++) {
var j = user.substring(i,i+1);
if (isNaN(j) == false) {
alert("姓名中不能包含数字。");
return false;
}
}
return true;
}
</script>
</head>
<body>
<table id="center" border="0" cellpadding="0" cellspacing="3">
<tr>
<td colspan="2" style="padding-left:120px; font-weight:bold;">注册休闲网</td>
</tr>
<form action="" method="post" onsubmit="return check();" id="myForm">
<tr>
<td class="right">您的email:</td>
<td><input id="email" type="text"/></td>
</tr>
<tr>
<td class="right">输入密码:</td>
<td><input id="pwd" type="password"/></td>
</tr>
<tr>
<td class="right">再输入一遍密码:</td>
<td><input id="repwd" type="password"/></td>
</tr>
<tr>
<td class="right">您的姓名:</td>
<td><input id="user" type="text"/></td>
</tr>
<tr>
<td colspan="2" style="text-align:center"><input type="submit" value="提交"/></td>
</tr>
</form>
</table>
</body>
</html>
执行结果：
标签：
原文地址：http://my.oschina.net/u/2320342/blog/397080
