php汉字转码 GBK到Big5编码转换

<?
//php汉字转码
class qswhBig5{
 var $qswhData;
 function qswhBig5($filename="qswhBig5.php"){
  $this->qswhData=file($filename);
 }
 function qswhStr($gb,$fail="??"){
  /******(qiushuiwuhen 2002-9-6)******/
  $ret="";
  for($i=0;$i<strlen($gb);$i++){
   if(($p=ord(substr($gb,$i,1)))>127){
    $q=ord(substr($gb,++$i,1));
    $tmp=$this->qswhData[$p-128];
    for($j=0;$j<strlen($tmp);$j+=6)if(($k=hexdec(substr($tmp,$j,2)))>=$q)break;
    if($k==$q)$q=chr(hexdec(substr($tmp,$j+2,2))).chr(hexdec(substr($tmp,$j+4,2)));
    else if($fail=="")$q=chr($p).chr($q); else $q=$fail;
   }
   else
    $q=chr($p);
   $ret.=$q;
  }
  return $ret;
 }
 function qswhFile($filename,$fail="??"){
  /******(qiushuiwuhen 2002-9-6)******/
  if(!file_exists($filename.".qswh"))copy($filename,$filename.".qswh");
  $fp=fopen($filename,"r+");
  $tmp=fread($fp,filesize($filename));
  rewind($fp);
  fwrite($fp,$this->qswhStr($tmp,$fail));
  fclose($fp);
 }
 
 function qswhDir($dirname,$fail="??"){
  /******(qiushuiwuhen 2002-9-6)******/
  $d = dir($dirname);
  while($entry=$d->read()) {
   if($entry=="."||$entry=="..")continue;
   $entry=$dirname."/".$entry;
   if(is_dir($entry))
       $this->qswhDir($entry,$fail);
      else{
       if(substr($entry,-5)!=".qswh")$this->qswhFile($entry,$fail);
      }
  }
  $d->close();
  return $c;
 }
 
}

$words="秋水无恨";
$qswh=new qswhBig5("qswhBig5.php"); //qswhBig5.php,可省参数

echo("<xmp>请选择编码Big5查看:".$qswh->qswhStr($words));
echo("/n编码一目录:".$qswh->qswhDir("test"));
echo("/n编码一文件:".$qswh->qswhFile("index.htm"));