Regular Expression Matching Issue

[tomtimms]

I have a form where a user types in their web address and I want to check the database to make sure it doesnt exists.  Here is my function.

 

    function valid_url_exist ($str)

    {

        return (preg_match('@^(?:https://\www.|http://\www.|http://|https://)?([^/]+)@i', $str, $matches));

    }

 

and here is my check

 

    if(valid_url_exist($url) === valid_url_exist($db_url) ) {

       

   

        $error .='This site already exists in our database';

       

    } 

 

I insert http://www.mysite.com and it takes (doesn't exist), however if I go and try and insert http://mysite.com it takes and the error check doesn't work.  It only works on exact matches so if i try http://www.mysite.com it tells me it exists.  Anyone have an idea?

 

[Ken2k7]

Oh wow. That regexp is a bit awkward, but you need to escape those dots.

#^https?://(www\.)?[^/]+#i

 

I'm not sure how useful this line is:

if(valid_url_exist($url) === valid_url_exist($db_url) ) {

 

You're checking if a valid url matches another valid url? So as long as both are valid urls, it's good? Why not just do this then?

if(valid_url_exist($url) && valid_url_exist($db_url) ) {

[tomtimms]

Yeah I am checking to see if the URL provided matches the URL in the database.

[Ken2k7]

Uh no.  - preg_match. preg_match returns an int that says how many times the pattern matches. So, it doesn't determine if the URLs are the same. It just checks if they are of any URL.

[tomtimms]

Anyone have any insight on how this could be accomplished?

[Ken2k7]

strcmp

[dirkers]

Just a word of caution ... you can't necessarily assume that all those URL variations point to the same site. Although it is often the case, all of the following could be serving different sites:

 

• http://somesite.com
  
• https://somesite.com
  
• http://www.somesite.com
  
• https://www.somesite.com
  

 

-D