一個用PHP實現的UBB類！

ubb   <?php
  /*
  如有轉載，請註明作者
  
  作者: 何志強
  檔案: ubb.php
  備忘: 說是改進，其實核心函數parse()已經完全重寫了，而且思路也是不一樣的。
  不過仍是受何志強的例子的啟發，而且測試的例子還有URLCHECK等幾個函數也是沿用的何志強的程式，謝謝何志強。
  目前還沒有顏色的功能，但我會加入的。
  如果在程式上有什麼BUG或不便的地方，請給我MAIL。
  謝謝！
  改進功能:
  對字串進行UBB編碼,該類目前只支援下列幾個簡單且實用的編碼:
  1. URL褳接
  http://www.phpexe.com/
  http://頭可以不需要
  如phpexe.com也是可以的。
  2. Email褳接
  demo@163.net
  3. 圖片褳接
  
  同URL連結一樣，前面的http也可以不要。
  4. 文字方面
  粗體字
  斜體字
  加底線
  
  1號標題字
  ...
  6號標題字
  
  
  
  [tt][/tt]
  [s][/s]
  
  [em][/em]
  [strong][/strong]
  
  [samp][/samp]
  [kbd][/kbd]
  [var][/var]
  [dfn][/dfn]
  [cite][/cite]
  
  
  
  注意以下幾點:
  1. url,email,img等標籤是不分大小寫.
  2. 在標籤中不允許有TAB鍵出現，但空格允許。
  3. 該類要調用htmlencode,htmlencode4textarea,emailcheck函數和urlcheck類.
  4. 修改後支援嵌套，但url,email,img這三個標籤不是允許嵌套的。
  技術資料:
  Ultimate Bulletin Board
  http://www.ultimatebb.com/
  What is UBB Code
  http://www.scriptkeeper.com/ubb/ubbcode.html
  */
  
  include("urlcheck.php");
  include("otherfunc.php"); //這兩個檔案的內容，附在最後。
  
  //ubbcode類
  class ubbcode{
  var $call_time=0;
  //可處理標籤及處理函數對應表
  var $tags = array( //小寫標籤 => 對應的處理函數
  'url' => '$this->url',
  'email' => '$this->email',
  'img' => '$this->img',
  'b' => '$this->simple',
  'i' => '$this->simple',
  'u' => '$this->simple',
  'tt' => '$this->simple',
  's' => '$this->simple',
  'strike' => '$this->simple',
  'h1' => '$this->simple',
  'h2' => '$this->simple',
  'h3' => '$this->simple',
  'h4' => '$this->simple',
  'h5' => '$this->simple',
  'h6' => '$this->simple',
  'sup' => '$this->simple',
  'sub' => '$this->simple',
  'em' => '$this->simple',
  'strong' => '$this->simple',
  'code' => '$this->simple',
  'samp' => '$this->simple',
  'kbd' => '$this->simple',
  'var' => '$this->simple',
  'dfn' => '$this->simple',
  'cite' => '$this->simple',
  'small' => '$this->simple',
  'big' => '$this->simple',
  'blink' => '$this->simple'
  );
  //url褳接屬性
  var $attr_url;
  //url合法性檢查對象
  var $urlcheck;
  
  function ubbcode($attr_url){
  $this->attr_url = ''.$attr_url;
  $this->urlcheck = new urlcheck();
  }
  
  //對$str進行UBB編碼解析
  function parse($str){
  $this->call_time++;
  $parse = ''.htmlencode($str);
  
  $ret = '';
  while(true){
  $eregi_ret=eregi("\[[#]{0,1}[[:alnum:]]{1,7}\]",$parse,$eregi_arr); //尋找[xx]
  if(!$eregi_ret){
  $ret .= $parse;
  break; //如果沒有，返回
  }
  $pos = @strpos($parse,$eregi_arr[0]);
  $tag_len=strlen($eregi_arr[0])-2;//標記長度
  $tag_start=substr($eregi_arr[0],1,$tag_len);
  $tag=strtolower($tag_start);
  
  if((($tag=="url") or ($tag=="email") or ($tag=="img")) and ($this->call_time>1)){
  echo $this->call_time."<br>";
  return $parse;//如果不能是不能嵌套的標記，直接返回
  }
  
  $parse2 = substr($parse,0,$pos);//標記之前
  $parse = substr($parse,$pos+$tag_len+2);//標記之後
  if(!isset($this->tags[$tag])){
  echo "$tag_start<br>";
  $ret .= $parse2.'['.$tag_start.']';
  continue;//如果是不支援的標記
  }
  
  //尋找對對應的結束標記
  $eregi_ret=eregi("\[\/".$tag."\]",$parse,$eregi_arr);
  if(!$eregi_ret){
  $ret .= $parse2.'['.$tag_start.']';
  continue;//如果沒有對應該的結束標記
  }
  $pos=strpos($parse,$eregi_arr[0]);
  $value=substr($parse,0,$pos);//這是起止標記之間的內容
  $tag_end=substr($parse,$pos+2,$tag_len);
  $parse=substr($parse,$pos+$tag_len+3);//結束標記之後的內容
  
  if(($tag!="url") and ($tag!="email") and ($tag!="img")){
  $value=$this->parse($value);
  }
  
  $ret .= $parse2;
  eval('$ret .= '.$this->tags[$tag].'("'.$tag_start.'","'.$tag_end.'","'.$value.'");');
  }
  $this->call_time--;
  return $ret;
  }
  
  function simple($start,$end,$value){
  return '<'.$start.'>'.$value.'</'.$end.'>';
  }
  
  function url($start,$end,$value){
  $trim_value=trim($value);
  if (strtolower(substr($trim_value,0,7))!="http://")
  $trim_value="http://".$trim_value;
  if($this->urlcheck->check($trim_value)) return '<a href="'.$trim_value.'" '.$this->attr_url.'>'.$value.'</a>';
  else return '['.$start.']'.$value.'[/'.$end.']';
  }
  
  function email($start,$end,$value){
  if(emailcheck($value)) return '<a href="mailto:'.$value.'">'.$value.'</a>';
  else return '['.$start.']'.$value.'[/'.$end.']';
  }
  
  function img($start,$end,$value){
  $trim_value=trim($value);
  if ((strtolower(substr($trim_value,0,7))!="http://") or ($this->urlcheck->check($trim_value)))
  return '<img src="'.$trim_value.'"></img>';
  else return '['.$start.']'.$value.'[/'.$end.']';
  }
  }
  
  //測試
  echo '<html>';
  echo '<head><title>測試</title></head>';
  echo '<body>';
  echo '<form action="'.str2url($PATH_INFO).'" method="post">';
  echo '<textarea cols="100" rows="10" name="ubb">'.htmlencode4textarea($ubb).'</textarea><br>';
  echo '<input type="submit" value="轉換">';
  echo '</form>';
  
  if(isset($ubb)){
  $ubbcode = new ubbcode('target="_blank"');
  echo '<hr>'.$ubbcode->parse($ubb);
  }
  
  echo '</body>';
  echo '</html>';
  
  ?>
  
  檔案urlcheck.php的內容
  <?php
  //urlcheck.php
  class urlcheck{
  var $regex = array(//協議名(注意在這裡必須寫成小寫) => 對應的Regex
  'ftp' => '$this->ftpurl',
  'file' => '$this->fileurl',
  'http' => '$this->httpurl',
  'https' => '$this->httpurl',
  'gopher' => '$this->gopherurl',
  'news' => '$this->newsurl',
  'nntp' => '$this->nntpurl',
  'telnet' => '$this->telneturl',
  'wais' => '$this->waisurl'
  );
  
  var $lowalpha;
  var $hialpha;
  var $alpha;
  var $digit;
  var $safe;
  var $extra;
  var $national;
  var $punctuation;
  var $reserved;
  var $hex;
  var $escape;
  var $unreserved;
  var $uchar;
  var $xchar;
  var $digits;
  
  var $urlpath;
  var $password;
  var $user;
  var $port;
  var $hostnumber;
  var $alphadigit;
  var $toplabel;
  var $domainlabel;
  var $hostname;
  var $host;
  var $hostport;
  var $login;
  
  //ftp
  var $ftptype;
  var $fsegment;
  var $fpath;
  var $ftpurl;
  
  //file
  var $fileurl;
  
  //http,https
  var $search;
  var $hsegment;
  var $hpath;
  var $httpurl;
  
  //gopher
  var $gopher_string;
  var $selector;
  var $gtype;
  var $gopherurl;
  
  //news
  var $article;
  var $group;
  var $grouppart;
  var $newsurl;
  
  //nntp
  var $nntpurl;
  
  //telnet
  var $telneturl;
  
  //wais
  var $wpath;
  var $wtype;
  var $database;
  var $waisdoc;
  var $waisindex;
  var $waisdatabase;
  var $waisurl;
  
  function check($url){
  $pos = @strpos($url,':',1);
  if($pos<1) return false;
  $prot = substr($url,0,$pos);
  if(!isset($this->regex[$prot])) return false;
  eval('$regex = '.$this->regex[$prot].';');
  return ereg('^'.$regex.'$',$url);
  }
  
  function urlcheck(){
  $this->lowalpha = '[a-z]';
  $this->hialpha = '[A-Z]';
  $this->alpha = '('.$this->lowalpha.'|'.$this->hialpha.')';
  $this->digit = '[0-9]';
  $this->safe = '[$.+_-]';
  $this->extra = '[*()\'!,]';
  $this->national = '([{}|\^~`]|\\[|\\])';
  $this->punctuation = '[<>#%"]';
  $this->reserved = '[?;/:@&=]';
  $this->hex = '('.$this->digit.'|[a-fA-F])';
  $this->escape = '(%'.$this->hex.'{2})';
  $this->unreserved = '('.$this->alpha.'|'.$this->digit.'|'.$this->safe.'|'.$this->extra.')';
  $this->uchar = '('.$this->unreserved.'|'.$this->escape.')';
  $this->xchar = '('.$this->unreserved.'|'.$this->reserved.'|'.$this->escape.')';
  $this->digits = '('.$this->digit.'+)';
  
  $this->urlpath = '('.$this->xchar.'*)';
  $this->password = '(('.$this->uchar.'|[?;&=]'.')*)';
  $this->user = '(('.$this->uchar.'|[?;&=]'.')*)';
  $this->port = $this->digits;
  $this->hostnumber = '('.$this->digits.'.'.$this->digits.'.'.$this->digits.'.'.$this->digits.')';
  $this->alphadigit = '('.$this->alpha.'|'.$this->digit.')';
  $this->toplabel = '('.$this->alpha.'|('.$this->alpha.'('.$this->alphadigit.'|-)*'.$this->alphadigit.'))';
  $this->domainlabel = '('.$this->alphadigit.'|('.$this->alphadigit.'('.$this->alphadigit.'|-)*'.$this->alphadigit.'))';
  $this->hostname = '(('.$this->domainlabel.'\\.)*'.$this->toplabel.')';
  $this->host = '('.$this->hostname.'|'.$this->hostnumber.')';
  $this->hostport = '('.$this->host.'(:'.$this->port.')?)';
  $this->login = '(('.$this->user.'(:'.$this->password.')?@)?'.$this->hostport.')';
  
  $this->ftptype = '[aidAID]';
  $this->fsegment = '(('.$this->uchar.'|[?:@&=])*)';
  $this->fpath = '('.$this->fsegment.'(/'.$this->fsegment.')*)';
  $this->ftpurl = '([fF][tT][pP]://'.$this->login.'(/'.$this->fpath.'(;[tT][yY][pP][eE]='.$this->ftptype.')?)?)';
  
  $this->fileurl = '([fF][iI][lL][eE]://('.$this->host.'|[lL][oO][cC][aA][lL][hH][oO][sS][tT])?/'.$this->fpath.')';
  
  $this->search = '(('.$this->uchar.'|[;:@&=])*)';
  $this->hsegment = '(('.$this->uchar.'|[;:@&=])*)';
  $this->hpath = '('.$this->hsegment.'(/'.$this->hsegment.')*)';
  $this->httpurl = '([hH][tT][tT][pP][sS]?://'.$this->hostport.'(/'.$this->hpath.'([?]'.$this->search.')?)?)';
  
  $this->gopher_string = '('.$this->xchar.'*)';
  $this->selector = '('.$this->xchar.'*)';
  $this->gtype = $this->xchar;
  $this->gopherurl = '([gG][oO][pP][hH][eE][rR]://'.$this->hostport.'(/('.$this->gtype.'('.$this->selector.'(%09'.$this->search.'(%09'.$this->gopher_string.')?)?)?)?)?)';
  
  $this->article = '(('.$this->uchar.'|[;/?:&=])+@'.$this->host.')';
  $this->group = '('.$this->alpha.'('.$this->alpha.'|'.$this->digit.'|[-.+_])*)';
  $this->grouppart = '([*]|'.$this->group.'|'.$this->article.')';
  $this->newsurl = '([nN][eE][wW][sS]:'.$this->grouppart.')';
  
  $this->nntpurl = '([nN][nN][tT][pP]://'.$this->hostport.'/'.$this->group.'(/'.$this->digits.')?)';
  
  $this->telneturl = '([tT][eE][lL][nN][eE][tT]://'.$this->login.'/?)';
  
  $this->wpath = '('.$this->uchar.'*)';
  $this->wtype = '('.$this->uchar.'*)';
  $this->database = '('.$this->uchar.'*)';
  $this->waisdoc = '([wW][aA][iI][sS]://'.$this->hostport.'/'.$this->database.'/'.$this->wtype.'/'.$this->wpath.')';
  $this->waisindex = '([wW][aA][iI][sS]://'.$this->hostport.'/'.$this->database.'[?]'.$this->search.')';
  $this->waisdatabase = '([wW][aA][iI][sS]://'.$this->hostport.'/'.$this->database.')';
  $this->waisurl = '('.$this->waisdatabase.'|'.$this->waisindex.'|'.$this->waisdoc.')';
  }
  }
  
  ?>
  
  
  檔案otherfunc.php的內容
  <?php
  //otherfunc.php
  function htmlencode($str){
  $str = (string)$str;
  
  $ret = '';
  $len = strlen($str);
  $nl = false;
  for($i=0;$i<$len;$i++){
  $chr = $str[$i];
  switch($chr){
  case '<':
  $ret .= '<';
  $nl = false;
  break;
  case '>':
  $ret .= '>';
  $nl = false;
  break;
  case '"':
  $ret .= '"';
  $nl = false;
  break;
  case '&':
  $ret .= '&';
  $nl = false;
  break;
  /*
  case ' ':
  $ret .= ' ';
  $nl = false;
  break;
  */
  case chr(9):
  $ret .= '    ';
  $nl = false;
  break;
  case chr(10):
  if($nl) $nl = false;
  else{
  $ret .= '<br>';
  $nl = true;
  }
  break;
  case chr(13):
  if($nl) $nl = false;
  else{
  $ret .= '<br>';
  $nl = true;
  }
  break;
  default:
  $ret .= $chr;
  $nl = false;
  break;
  }
  }
  
  return $ret;
  }
  
  
  function htmlencode4textarea($str){
  $str = (string)$str;
  
  $ret = '';
  $len = strlen($str);
  for($i=0;$i<$len;$i++){
  $chr = $str[$i];
  switch($chr){
  case '<':
  $ret .= '<';
  break;
  case '>':
  $ret .= '>';
  break;
  case '"':
  $ret .= '"';
  break;
  case '&':
  $ret .= '&';
  break;
  case ' ':
  $ret .= ' ';
  break;
  case chr(9):
  $ret .= '    ';
  break;
  default:
  $ret .= $chr;
  break;
  }
  }
  
  return $ret;
  }
  
  function emailcheck($email){
  $ret=false;
  if(strstr($email, '@') && strstr($email, '.')){
  if(eregi("^([_a-z0-9]+([\\._a-z0-9-]+)*)@([a-z0-9]{2,}(\\.[a-z0-9-]{2,})*\\.[a-z]{2,3})$", $email)){
  $ret=true;
  }
  }
  return $ret;
  }
  
  function str2url($path){
  return eregi_replace("%2f","/",urlencode($path));
  }
  ?>