首页 / 正则表达式 / Javascript Validation for email（正则表达式） 英文翻译

Try testing the following form with valid and invalid email addresses. The
code uses javascript to match the users input with a regular expression.
函数代码：
复制代码 代码如下:
function validate（form_id,email） {
var reg = /^（[A-Za-z0-9_-.]）+@（[A-Za-z0-9_-.]）+.（[A-Za-z]{2,4}）$/;
var address = document.forms[form_id].elements[email].value;
if（reg.test（address） == false） {
alert（"Invalid Email Address"）;
return false;
}
}

In the forms ‘onsubmit" code call javascript:return validate（‘form_id","email_field_id"）
使用方法：
复制代码 代码如下:
<form id="form_id" method="post" action="action.php" onsubmit="javascript:return validate（"form_id","email"）;">
<input type="text" id="email" name="email" />
<input type="submit" value="Submit" />
</form>

You should not rely purely on client side validation on your website / web application, if the user has javascript disabled this will not work. Always validate on the server.
from: http://www.white-hat-web-design.co.uk/blog/javascript-validation/