link exchange

Link exchange, så når en bruger f.eks. skriver www.udvikleren.dk så bliver det lavet om til et link?

Jeg har før brugt dette script:

tagster_lib.php

<?php 
/* 
    File : tagster_lib.php 
    Version : 3.0 
    Date : September 22nd, 2002 
    Author : Lars B. Jensen, lars.jensen@ljweb.com 

    Module Description 
    Module to transform URL and E-Mail addresses into clickable links. 

    Instruction 
    To utilize the tagster_lib library, copy this file to a location on your server. Include the 
    library into your php document or template. 
    Use the function tagster_format to extract and modify all links and emails in a given string. 
    The parameters $target handling the target for links and $class for handling css on <a tags are 
    both optional. 
     
    Example     
    include('lib/tagster_lib.php'); 
    $str = tagster_format($str, "_blank", "mystyle"); 

    Note 
    This module library has support for the scandinavian specialchars æ, ø and å. 


    Public Functions 
    --------------------------------------------------------------´ 
    function tagster_format($str, $target, $css_class, $fixlongword) 
    function tagster_url($str, $target, $class) 
    function tagster_email($str, $class) 

    Private Functions 
    --------------------------------------------------------------´ 
    function tagster_fix_endchar($str) 
    function tagster_expand($str) 
    function tagster_reduce($str) 
    function tagster_fix_longword($str, $maxlen) 
*/ 

    function tagster_format($str, $target="_blank", $css_class="", $fixlongword = 0) { 
        $str = str_replace("&", "&", $str); 
        $str = str_replace("<", "<", $str); 
        $str = str_replace(">", ">", $str); 
        $str = tagster_url($str, $target, $css_class); 
        $str = tagster_email($str, $css_class); 
        $str = tagster_fix_endchar($str); 
        $str = str_replace("  ", "  ", $str); 
        $str = str_replace("\\t", "    ", $str); 
        $str = str_replace("\\r", "", $str); 
        $str = str_replace("\\n", "<br>", $str); 
         
        if ($fixlongword != 0) $str = tagster_fix_longword($str, $fixlongword); 
        return $str; 
    } 


    function tagster_url($str, $target, $css_class) { 
        $ins_str = ""; 
        if ($css_class) $ins_str .= " class=\\"".$css_class."\\""; 
        if ($target) $ins_str .= " target=\\"".$target."\\""; 
        $str = tagster_expand($str); 
        $str = preg_replace ("/(ftp|http|https|telnet|news|nntp|file|irc):\\/\\/([a-z0-9~#%@&:;=!',_æøå\\(\\)\\?\\/\\.\\-\\+\\[\\]\\|\\*\\$\\^\\{\\}]+)/i", "<a href=\\"\\\\1://\\\\2\\"".$ins_str.">\\\\1://\\\\2</a>", $str); 
        $str = preg_replace ("/(\\s|tp\\:|\\(|\\[|\\>)(www\\.)([a-z0-9~#%@&:;=!',_æøå\\(\\)\\?\\/\\.\\-\\+\\[\\]\\|\\*\\$\\^\\{\\}]+)/i", "\\\\1<a href=\\"http://\\\\2\\\\3\\"".$ins_str.">\\\\2\\\\3</a>", $str); 
        $str = preg_replace ("/(\\s|tp\\:|\\(|\\[|\\>)(ftp\\.)([a-z0-9~#%@&:;=!',_æøå\\(\\)\\?\\/\\.\\-\\+\\[\\]\\|\\*\\$\\^\\{\\}]+)/i", "\\\\1<a href=\\"ftp://\\\\2\\\\3\\"".$ins_str.">\\\\2\\\\3</a>", $str); 
        return tagster_reduce($str); 
    } 


    function tagster_email($str, $css_class="") { 
        $ins_class = ""; 
        if ($css_class) $ins_class = " class=\\"".$css_class."\\""; 
        $str = tagster_expand($str); 
        $str = preg_replace ("/([\\s\\"])([\\w\\.\\-_]+)@([\\w\\-_]+)\\.([\\w\\.\\-_]+)/i", "\\\\1<a href=\\"mailto:\\\\2@\\\\3.\\\\4\\"".$ins_class.">\\\\2@\\\\3.\\\\4</a>", $str); 
        return tagster_reduce($str); 
    } 


    function tagster_fix_endchar($str) { 
        $str = preg_replace ("/([\\'\\"\\)\\]\\.\\,\\?\\!]+)\\">/i", "\\">", $str); 
        $str = preg_replace ("/([\\'\\"\\)\\]\\.\\,\\?\\!]+)\\" (target|class)=\\"/i", "\\" \\\\2=\\"", $str); 
        $str = preg_replace ("/([\\'\\"\\)\\]\\.\\,\\?\\!]+)<\\/a>/i", "</a>\\\\1", $str); 
        return $str; 
    } 

    function tagster_fix_longword($str, $maxlen = 10) { 
        $sw = 0; 
        $in_tag = false; 
        $str_size = strlen($str); 
        $res = ""; 

        for ($i=0; $i<$str_size; $i++){ 
            if ($str[$i] == '<') $in_tag = true; 
            else if ($str[$i] == ' ') $sw = 0; 

            if (!$in_tag && (($sw++) > $maxlen)) { 
                $res .= '­'; 
                $sw = 0; 
            } 
             
            if ($str[$i] == '>') $in_tag = false; 
            $res .= $str[$i]; 
        } 
         
        return $res; 
    } 

    function tagster_expand($str) { 
        return " ".$str." "; 
    } 

    function tagster_reduce($str) { 
        return substr($str, 1, -1); 
    } 
?>

Prøv at lede på nettet efter et andet script af ham. Jeg kan huske at han lavede et script der kunne tjekke om e-mails var gyldige og eksistere, og vist nok også hjemmesider. Desværre er hans egen hjemmeside lukket ned nu, så du må nok igang med google.