电子邮件验证 - 我的正则表达式代码有什么问题？

Question

I'm trying to validate an email address using preg_match..

But i'm getting this error..

Warning: preg_match(): Unknown modifier '+'

This is my code

preg_match("[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", $email, $matches);

Can someone tell me what is wrong with my regex?

Thanks

Answer 1

You need to put delimiters around the regex when you use preg_match . The standard is / . If you use the delimiter in the expression, you have to escape it.

preg_match("/[a-z0-9!#$%&'*+\/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+\/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?/", $email, $matches);

You could also consider using

filter_var($email, FILTER_VALIDATE_EMAIL);