汉字转换拼音的有关问题

function getfirstchar($s0){         $firstchar_ord=ord(strtoupper($s0{0}));         if (($firstchar_ord>=65 and $firstchar_ord<=91)or($firstchar_ord>=48 and $firstchar_ord<=57)) return $s0{0};         $s0=iconv("UTF-8","gb2312", $s0);        $s=$s0;         $asc=ord($s{0})*256+ord($s{1})-65536;         if($asc>=-20319 and $asc<=-20284)return "A";         if($asc>=-20283 and $asc<=-19776)return "B";         if($asc>=-19775 and $asc<=-19219)return "C";         if($asc>=-19218 and $asc<=-18711)return "D";         if($asc>=-18710 and $asc<=-18527)return "E";         if($asc>=-18526 and $asc<=-18240)return "F";         if($asc>=-18239 and $asc<=-17923)return "G";         if($asc>=-17922 and $asc<=-17418)return "H";         if($asc>=-17417 and $asc<=-16475)return "J";         if($asc>=-16474 and $asc<=-16213)return "K";         if($asc>=-16212 and $asc<=-15641)return "L";         if($asc>=-15640 and $asc<=-15166)return "M";         if($asc>=-15165 and $asc<=-14923)return "N";         if($asc>=-14922 and $asc<=-14915)return "O";         if($asc>=-14914 and $asc<=-14631)return "P";         if($asc>=-14630 and $asc<=-14150)return "Q";         if($asc>=-14149 and $asc<=-14091)return "R";         if($asc>=-14090 and $asc<=-13319)return "S";         if($asc>=-13318 and $asc<=-12839)return "T";         if($asc>=-12838 and $asc<=-12557)return "W";         if($asc>=-12556 and $asc<=-11848)return "X";         if($asc>=-11847 and $asc<=-11056)return "Y";         if($asc>=-11055 and $asc<=-10247)return "Z";     }