php取出字符串（包括汉字）首字母函数

function getfirstchar($s0){
if(ord($s0)>="1" and ord($s0)<=ord("z") ) { return strtoupper($s0); }
//$s=iconv("UTF-8","gb2312", $s0); 如果需要转换为utf-8的话
$s=$s0;//无需转换的情况
$asc=ord($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 0;
}
echo getfirstchar("你好");

?>

以上就介绍了php取出字符串（包括汉字）首字母函数，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。