php字符转码解决新浪抓取资料乱码的问题

function unescape($str) {
  $str = rawurldecode($str);
  preg_match_all("/(?:%u.{4})|.+/",$str,$r);
  $ar = $r[0];
  foreach($ar as $k=>$v) {
    if(substr($v,0,2) == '%u' && strlen($v) == 6)
      $ar[$k] = iconv("UCS-2","utf-8",pack("H4",substr($v,-4)));
  }
  return join("",$ar);
}

有点小问题，又换一个函数，好像功能要强大一些。

function unescape($str) {
  $str = rawurldecode($str);
  preg_match_all("/%u.{4}|.{4};|\d+;|\d+?|.+/U",$str,$r);
  $ar = $r[0];
  foreach($ar as $k=>$v) {
  if(substr($v,0,2) == "%u")
  $ar[$k] = iconv("UCS-2","utf-8",pack("H4",substr($v,-4)));
  elseif(substr($v,0,3) == "")
  $ar[$k] = iconv("UCS-2","utf-8",pack("H4",substr($v,3,-1)));
  elseif(substr($v,0,2) == "") {
  $ar[$k] = iconv("UCS-2","utf-8",pack("n",preg_replace("/[^\d]/","",$v)));
  }
}
return join("",$ar);
}

用了一段时间，发现在本地可以使用，但是我们的线上环境不能够使用。 线上是*nux，本地是XP了，还有，就是PHP版本不一样了。 后来，又在手册里面发现有一个类似的函数 而且还支持utf8，个人觉得应该通用性更好吧。

//php字符转码
function utf8RawUrlDecode ($source) {
   $decodedStr = "";
   $pos = 0;
   $len = strlen ($source);
   while ($pos        $charAt = substr ($source, $pos, 1);
       if ($charAt == '%') {
           $pos++;
           $charAt = substr ($source, $pos, 1);
           if ($charAt == 'u') {
               // we got a unicode character
               $pos++;
               $unicodeHexVal = substr ($source, $pos, 4);
               $unicode = hexdec ($unicodeHexVal);
               $entity = "". $unicode . ';';
               $decodedStr .= utf8_encode ($entity);
               $pos += 4;
           }
           else {
               // we have an escaped ascii character
               $hexVal = substr ($source, $pos, 2);
               $decodedStr .= chr (hexdec ($hexVal));
               $pos += 2;
           }
       } else {
           $decodedStr .= $charAt;
           $pos++;
       }
   }
   return $decodedStr;
}

使用此函数成功解决问题。