php 取汉字首字母

function getfirstchar($s0){  
 $fchar = ord($s0{0});
 if($fchar >= ord("A") and $fchar <= ord("z") )return strtoupper($s0{0});
 $s1 = iconv("UTF-8","gb2312", $s0);
 $s2 = iconv("gb2312","UTF-8", $s1);
 if($s2 == $s0){$s = $s1;}else{$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 $asc <= -17418) return "I";
 if($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";
 return null;
}

function pinyin($zh){
 $ret = "";
    $s1 = iconv("UTF-8","gb2312", $zh);
    $s2 = iconv("gb2312","UTF-8", $s1);
    if($s2 == $zh){$zh = $s1;}
 for($i = 0; $i < strlen($zh); $i++){
  $s1 = substr($zh,$i,1);
  $p = ord($s1);
  if($p > 160){
   $s2 = substr($zh,$i++,2);
   $ret .= getfirstchar($s2);
  }else{
   $ret .= $s1;
  }
 }
 return $ret;
}
echo "杜川 reload  by http://dcdc723.iteye.com
";
echo pinyin('杜川 by dcdc723');

?>

中文范围

 [\u4E00-\u9FA5\uf900-\ufa2d]