PHP获取中英文字符串的首字母

function getFirstCharter($str) { ???if (empty($str)) { ???????return ‘‘; ???} ???$fchar = ord($str{0}); ???if ($fchar >= ord(‘A‘) && $fchar <= ord(‘z‘)) return strtoupper($str{0}); ???$s1 = iconv(‘UTF-8‘, ‘gb2312‘, $str); ???$s2 = iconv(‘gb2312‘, ‘UTF-8‘, $s1); ???$s = $s2 == $str ? $s1 : $str; ???$asc = ord($s{0}) * 256 + ord($s{1}) - 65536; ???if ($asc >= -20319 && $asc <= -20284) return ‘A‘; ???if ($asc >= -20283 && $asc <= -19776) return ‘B‘; ???if ($asc >= -19775 && $asc <= -19219) return ‘C‘; ???if ($asc >= -19218 && $asc <= -18711) return ‘D‘; ???if ($asc >= -18710 && $asc <= -18527) return ‘E‘; ???if ($asc >= -18526 && $asc <= -18240) return ‘F‘; ???if ($asc >= -18239 && $asc <= -17923) return ‘G‘; ???if ($asc >= -17922 && $asc <= -17418) return ‘H‘; ???if ($asc >= -17417 && $asc <= -16475) return ‘J‘; ???if ($asc >= -16474 && $asc <= -16213) return ‘K‘; ???if ($asc >= -16212 && $asc <= -15641) return ‘L‘; ???if ($asc >= -15640 && $asc <= -15166) return ‘M‘; ???if ($asc >= -15165 && $asc <= -14923) return ‘N‘; ???if ($asc >= -14922 && $asc <= -14915) return ‘O‘; ???if ($asc >= -14914 && $asc <= -14631) return ‘P‘; ???if ($asc >= -14630 && $asc <= -14150) return ‘Q‘; ???if ($asc >= -14149 && $asc <= -14091) return ‘R‘; ???if ($asc >= -14090 && $asc <= -13319) return ‘S‘; ???if ($asc >= -13318 && $asc <= -12839) return ‘T‘; ???if ($asc >= -12838 && $asc <= -12557) return ‘W‘; ???if ($asc >= -12556 && $asc <= -11848) return ‘X‘; ???if ($asc >= -11847 && $asc <= -11056) return ‘Y‘; ???if ($asc >= -11055 && $asc <= -10247) return ‘Z‘; ???return null;}