Url submission Verification

[moola]

I have a form where users can submit urls.

How do I verify a url is submitted in these forms exactly:

[code]http://www.youtube.com/v/shgRSgYwBv0[/code]
or
[code]http://www.youtube.com/watch?v=shgRSgYwBv0[/code]\

else

Exit the script and prompt the user for a correct url.

[Orio]

Altough I am a regex newbie, I think this will do:

[code]<?php
$regex = "/^http:\/\/www\.youtube\.com\/((v\/[a-zA-Z0-9]+)|(watch\?v=[a-zA-Z0-9]+))$/"
if(!preg_match($regex, $url))
die("Invalid URL!");
else
{
//....
}

?>[/code]

Orio.

[effigy]

[code]
%^http://www\.youtube\.com/(?:v/|watch\?v=)[a-zA-Z0-9]{11}\z%
[/code]

The 11 is exact based on your examples. This may need to be tuned.

[moola]

Is there a way to have a variation on the 11 to adjust for less or more characters.

[effigy]

Yes. The valid syntax within the[tt] { } [/tt]quantifier is:

# for an exact match
#, for a minimal match
,# for a maximum match
#,# for a ranged match

See the links in my signature for more information.