自己写的一个UBB转换的函数

function ubb2xhtml($ubb)
{
$flash=<<<END
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
 codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" width="%1/$d" height="%2/$d">
 <param name="movie" value="%3/$s" />
 <param name="quality" value="high" />
 <embed src="%3/$s" width="%1/$d" height="%2/$d" quality="high" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer"></embed>
</object>
END;
 $match = array
 (
  '%/[url=([^/s]+)/](.*?)/[/url/]%s',
  '%/[email=([^/s])+/](.*?)/[/email/]%i',
  '%/[img width=(/d+) height=(/d+)/](.*?)/[/img/]%s',
  '%/[img=([^/s]+)///]%s',
  '%/[flash width=(/d+) height=(/d+)/](.*?)/[/flash/]%se',
  '%/[(b|i|u|strike|sup|sub)/](.*?)/[//1/]%s',
  '%/[h([1-6])/](.*?)/[/h/1/]%s',
  '%/[hr///]%s',
  '%/[color=([^/s]+)/](.*?)/[/color/]%s',
  '%/[font=([^/"]+)/](.*?)/[/font/]%s',
  '%/[size=([^/s]+)/](.*?)/[/size/]%s',
  '%/[align=(center|right|left)/](.*?)/[/align/]%s',
  '%/[valign=(middle|top|bottom)/](.*?)/[/valign/]%s',
/*
  '%/[ul/](.*?)/[/ul/]%s',
  '%/[ul=(circle|disc|square)/](.*?)/[/ul/]%s',
  '%/[ol/](.*?)/[/ol/]%s',
  '%/[ol type=([aAiI1]) start=([a-zA-Z1-9])/](.*?)/[/ol/]%s',
  '%/[li/](.*?)/[/li/]%s',
*/
  '%/[table=([^/s]+?)/](.*?)/[/table/]%s',
  '%/[caption/](.*?)/[/caption/]%s',
  '%/[tr=([^/s]+?)/](.*?)/[/tr/]%s',
  '%/[th/](.*?)/[/th/]%s',
  '%/[td/](.*?)/[/td/]%s',
  '%/[note/](.*?)/[/note/]%s',
  '%/[quote=(.*?)/](.*?)/[/quote/]%s',
  '%/[code/](.*?)/[/code/]%s',
  '%[ ]{2}%s',  // make double-spaces truly double-spaces!
 );
    $replace = array
 (
  '<a href="/1" target="_blank">/2</a>',
  '<a href="mailto:/1" target="_blank">/2</a>',
  '<img src="/3" width="/1" height="/2" border="0" />',
  '<img src="/1" border="0" />',
  'sprintf("$flash", "/1", "/2", "/3")',
  '</1>/2<//1>',
  '<h/1>/2</h/1>',
  '<hr>/n',
  '<font color="/1">/2</font>',
  '<font face="/1">/2</font>',
  '<font size="/1">/2</font>',
  '<div align="/1">/2</font>',
  '<div valign="/1">/2</font>',
/*
  '<ul>/1</ul>',
  '<ul type="/1">/2</ul>',
  '<ol>/1</ol>',
  '<ol type="/1" start="/2">/3</ol>',
  '<li>/1</li>',
*/
  "<table class=/"$1/" cellspacing=/"1/">/n$2</table>",
  "/t<caption>$1</caption>/n",
  "/t<tr class=/"$1/">/n$2/t</tr>/n",
  "/t/t<th>$1</th>/n",
  "/t/t<td>$1</td>/n",
  '<div class="note"><span class="hint">发布者备注</span><hr />/1</div>',
  '<div class="quote"><span class="hint">引用</span>(来源: <a href="/1" target="_blank">/1</a>)<br />/2</div>',
  '<span class="hint" style="margin-left: 10px">代码</span><div class="code">/1</div>',
  '&nbsp; ',
 );
 if( preg_match('%/[table=(.*?)//table/]%s', $ubb, $tablecells) ) //如果有表格, 先去除单元格之间的多余空白
 {
  $bb=preg_replace('%/]([/r/n/s]*)/[%si', '][', $tablecells[1]);
  $ubb=str_replace($tablecells[1], $bb, $ubb);
 }
 $html = preg_replace($match, $replace, nl2br(htmlspecialchars($ubb)));
 $html = preg_replace('/<br //>/s*<(td|th|tr|table|ul|ol|li)/m', "/n".'</1', $html);
 return $html;
}