ricavare url in testo semplice

[emanueledg]

Su php.net (alla voce preg_replace del manuale) è stata postata una soluzione dall'utente marten_berglund at hotmail dot com (la funzione linkify), eccola applicata in un esempio:

function linkify($text) {
    $strip_lchrs = "[^\s\(\)\[\]\{\}\.\,\;\:\?\!]";      //Not these chars in beginning
    $strip_rchrs = "[^\s\(\)\[\]\{\}\.\,\;\:\?\!\d]";    //Not these chars in end

    $prot_pat = $strip_lchrs . "[\S]*\:\/\/[\S]*\.[\S]*" . $strip_rchrs;  //abc://de.fg
    $email_pat = $strip_lchrs . "[\S]*@[\S]*\.[\S]*" . $strip_rchrs;      //abc@de.fg
    $general_pat = $strip_lchrs . "[\S]*\.[\S]*" . $strip_rchrs;          //abc.de

    $preg_pattern = "/(" . $prot_pat . "|" . $email_pat . "|" . $general_pat . ")/ei";
    $preg_replace = "check_preg('$1')";
    return preg_replace($preg_pattern, $preg_replace, $text);
}

function check_preg($subpat) {
    //These abbr. should not be linked
    $exc_string = "/e\.g|i\.e|et\.c/i";
    //If it says abc://de.fg
    if (preg_match("/[\S]*\:\/\/[\S]*\.[\S]*/i", $subpat) == 1) {
        return "[url='" . $subpat . "']" . $subpat . "[/url]";
    }
    //If it says [email]abc@de.fg[/email]
    else if (preg_match("/[\S]*@[\S]*\.[\S]*/i", $subpat) == 1) {
        return "[email='" . $subpat . "']" . $subpat . "[/email]";
    }
    //If it says "e.g." don't link
    else if (preg_match($exc_string, $subpat) == 1) {
        return $subpat;
    }
    //If it says abc.de
    else
        return "[url='http://" . $subpat . "']" . $subpat . "[/url]";
}



$testo = "Scrivi in questa stringa plain text, url e mail addresses";
echo linkify($string);