php 中用 Javascript 进行客户端数据检验

这是一个检验用户EMAIL地址的例子，和以前众多的PHP正则表达式对应

<html>
<head>
<script language="Javascript1.2">
<!-- start hiding
function verifyAddress(obj)
{
// obtain form value into variable
var email = obj.email.value;
// define regex
var pattern = /^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(/.[a-zA-Z0-9_-])+/;
// test for pattern
flag = pattern.test(email);
if(flag)
{ alert("Ummmmm....that sounds good!");
return true;
}
else
{
alert("Hey - who do you think you're kidding?");
return false;
}
}
// stop hiding -->
</script>
</head>
<body>
<form onSubmit="return verifyAddress(this);">
<input name="email" type="text">
<input type="submit">
</form>
</body>
</html>