<?php

function ($params, $di) {

    // 准备函数

    function getFirstChar($s0) {

        $fchar = ord(substr($s0, 0, 1));

        if (($fchar >= ord("a") and $fchar <= ord("z")) or ($fchar >= ord("A") and $fchar <= ord("Z"))) return strtoupper(chr($fchar));

        $s = iconv("UTF-8", "GBK", $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";

        return null;

    }

    // 参数

    $string = $params['string'];

    $charlist = preg_split('/(?<!^)(?!$)/u', $string);

    return implode(array_map("getFirstChar", $charlist));

​

}