PHP 获取汉字拼音首字母大写

转自：http://www.thinkphp.cn/code/118.html

获取汉字首字母大写

function get_letter($string) {

$charlist = mb_str_split($string);

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

}

function mb_str_split($string) {

// Split at all position not after the start: ^

// and not before the end: $

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

}

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;

}