Possible Duplicates:
PHP validation/regex for URL
PHP regex for validating a URL
I am using
(((?:http|https):\/\/[a-zA-Z0-9\/\?=_#&%~-]+(\.[a-zA-Z0-9\/\?=_#&%~-]+)+)|(www(\.[a-zA-Z0-9\/\?=_#&%~-]+){2,}))
to validate URL in my script.
But my friend told me there is a problem with this URL:
http://www.example.com/example(200)aaaa.rar
How can I add "(" and ")" to my regexp statement?
Are there another characters should I put in my regexp?
PHP already has a way to validate URLs, filter_var, which will work better than your regex (which as I commented above, allows false positives):
$url = "http://www.example.com/example(200)aaaa.rar";
var_dump(filter_var($url, FILTER_VALIDATE_URL));
May i recommend this site: http://regexlib.com/ Click Browse at the top and select Uri button.
To answer your question though, (((?:http|https):\/\/[a-zA-Z0-9\/\?=#&%~-]+(.[a-zA-Z0-9\/\?=#&%~-]+)+)|(www(.[a-zA-Z0-9\/\?=_#&%~-\\)\\(]+){2,}))
Note the \) and \( towards the end. They must be escaped (prefixed with \\) as these are characters used for grouping within regex.
I believe the specification will answer your question RFC-2068, though you will need to unpack your BNF boots for the journey.
In summary, pretty much any character can be used after the the domain name, excepting the few reserved ones which must be escaped:
The BNF [in the RFC] includes national characters not allowed in valid URLs as specified by RFC 1738, since HTTP servers are not restricted in the set of unreserved characters allowed to represent the rel_path part of addresses, and HTTP proxies may receive requests for URIs not defined by RFC 1738
