PHP implementation code to obtain the first letter of Chinese characters (gb2312 encoding)

This article introduces how to use PHP to obtain the first letter of a Chinese character. The encoding format is gb2312. Friends in need can refer to it.

php gets the first letter of Chinese characters, code:

<?php
//取GB2312字符串首字母
//GBK汉字是按拼音顺序编码的
function get_letter($input){
$dict=array(
'a'=>0xB0C4,
'b'=>0xB2C0,
'c'=>0xB4ED,
'd'=>0xB6E9,
'e'=>0xB7A1,
'f'=>0xB8C0,
'g'=>0xB9FD,
'h'=>0xBBF6,
'j'=>0xBFA5,
'k'=>0xC0AB,
'l'=>0xC2E7,
'm'=>0xC4C2,
'n'=>0xC5B5,
'o'=>0xC5BD,
'p'=>0xC6D9,
'q'=>0xC8BA,
'r'=>0xC8F5,
's'=>0xCBF9,
't'=>0xCDD9,
'w'=>0xCEF3,
'x'=>0xD188,
'y'=>0xD4D0,
'z'=>0xD7F9,
);

$str_1 = substr($input, 0, 1);
if ($str_1 >= chr(0x81) && $str_1 <= chr(0xfe))    {
$num = hexdec(bin2hex(substr($input, 0, 2)));
foreach ($dict as $k=>$v){
if($v>=$num)
break;
}
return $k;
}
else{
return $str_1;
} //by bbs.it-home.org
}

echo get_letter('脚');
echo get_letter('本');
echo get_letter('学');
echo get_letter('堂');
echo get_letter('欢');
echo get_letter('迎');
echo get_letter('您');
echo get_letter('网站编程');
?>

This is a pretty good piece of code, especially suitable for taking the first letter in the title and generating a list of articles classified by letters.