Alec Smart Alec Smart - 11 months ago 51
PHP Question

Php parse links/emails

I am wondering if there is a simple snippet which converts links of any kind:

http://www.cnn.com to <a href="http://www.cnn.com">http://www.cnn.com</a>
cnn.com to <a href="http://www.cnn.com">cnn.com</a>
www.cnn.com to <a href="http://www.cnn.com">www.cnn.com</a>
abc@def.com to to <a href="mailto:mailto:abc@def.com">mailto:abc@def.com</a>


I do not want to use any PHP5 specific library.

Thank you for your time.

UPDATE I have updated the above text to what i want to convert it to. Please note that the href tag and the text are different for case 2 and 3.

UPDATE2 Hows does gmail chat do it? Theirs is pretty smart and works only for real domains names. e.g. a.ly works but a.cb does not work.

Answer Source

yes , http://www.gidforums.com/t-1816.html

<?php
/**
   NAME        : autolink()
   VERSION     : 1.0
   AUTHOR      : J de Silva
   DESCRIPTION : returns VOID; handles converting
                 URLs into clickable links off a string.
   TYPE        : functions
   ======================================*/

function autolink( &$text, $target='_blank', $nofollow=true )
{
  // grab anything that looks like a URL...
  $urls  =  _autolink_find_URLS( $text );
  if( !empty($urls) ) // i.e. there were some URLS found in the text
  {
    array_walk( $urls, '_autolink_create_html_tags', array('target'=>$target, 'nofollow'=>$nofollow) );
    $text  =  strtr( $text, $urls );
  }
}

function _autolink_find_URLS( $text )
{
  // build the patterns
  $scheme         =       '(http:\/\/|https:\/\/)';
  $www            =       'www\.';
  $ip             =       '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}';
  $subdomain      =       '[-a-z0-9_]+\.';
  $name           =       '[a-z][-a-z0-9]+\.';
  $tld            =       '[a-z]+(\.[a-z]{2,2})?';
  $the_rest       =       '\/?[a-z0-9._\/~#&=;%+?-]+[a-z0-9\/#=?]{1,1}';            
  $pattern        =       "$scheme?(?(1)($ip|($subdomain)?$name$tld)|($www$name$tld))$the_rest";

  $pattern        =       '/'.$pattern.'/is';
  $c              =       preg_match_all( $pattern, $text, $m );
  unset( $text, $scheme, $www, $ip, $subdomain, $name, $tld, $the_rest, $pattern );
  if( $c )
  {
    return( array_flip($m[0]) );
  }
  return( array() );
}

function _autolink_create_html_tags( &$value, $key, $other=null )
{
  $target = $nofollow = null;
  if( is_array($other) )
  {
    $target      =  ( $other['target']   ? " target=\"$other[target]\"" : null );
    // see: http://www.google.com/googleblog/2005/01/preventing-comment-spam.html
    $nofollow    =  ( $other['nofollow'] ? ' rel="nofollow"'            : null );     
  }
  $value = "<a href=\"$key\"$target$nofollow>$key</a>";
} 

?>