Question

The code below detects URL’s in a body of text and wraps them in tags.

 function link_it($text)  
    {

        $text= preg_replace("/(^|[\n ])([\w]*?)((ht|f)tp(s)?:\/\/[\w]+[^ \,\"\n\r\t<]*)/is", "$1$2<a href=\"$3\" >$3</a>", $text);  
        $text= preg_replace("/(^|[\n ])([\w]*?)((www|ftp|m)\.[^ \,\"\t\n\r<]*)/is", "$1$2<a href=\"http://$3\" >$3</a>", $text);  
        $text= preg_replace("/(^|[\n ])([a-z0-9&\-_\.]+?)@([\w\-]+\.([\w\-\.]+)+)/i", "$1<a href=\"mailto:$2@$3\">$2@$3</a>", $text);  
        return($text);  
    }  

I would like it so that if a user types a url (detected via the function above) with a specific domain of (flickr|youtube|vimeo) etc the function adds the class “embed to the tag template, otherwise it leaves it classless.

e.g.

‘this is the website http://www.google.com’ would return:

this is the website <a href="http://www.google.com">http://www.google.com</a>

but ‘this is the website http://www.flickr.com’ would return

this is the website <a href="http://www.flickr.com" class="embed">http://www.flickr.com</a>

How would I go about adding this into the function?

Answer 1

Use preg_replace_callback() for this. In your callback function, match the URL against some set of URLs that should have the embed class, and if it matches, include the class attribute definition, otherwise don’t.