PHP Development Tips (7) - Code Example for Obtaining the First Letter of Pinyin of Chinese Characters

<?php  
  
/** 
 * ======================================= 
 * Created by Zhihua_W. 
 * Author: Zhihua_W 
 * Date: 2016/12/6 0007 
 * Time: 上午 8:46 
 * Project: PHP开发小技巧 
 * Power: 获取中文字符拼音首字母 
 * ======================================= 
 */  
  
/** 
 * 获取中文字符拼音首字母 
 * @param $str 中文字符 
 * @return null|string 
 */  
function getFirstCharter($str)  
{  
    if (empty($str)) {  
        return &#39;&#39;;  
    }  
    $fchar = ord($str{0});  
    if ($fchar >= ord(&#39;A&#39;) && $fchar <= ord(&#39;z&#39;)) return strtoupper($str{0});  
    $s1 = iconv(&#39;UTF-8&#39;, &#39;gb2312&#39;, $str);  
    $s2 = iconv(&#39;gb2312&#39;, &#39;UTF-8&#39;, $s1);  
    $s = $s2 == $str ? $s1 : $str;  
    $asc = ord($s{0}) * 256 + ord($s{1}) - 65536;  
    if ($asc >= -20319 && $asc <= -20284) return &#39;A&#39;;  
    if ($asc >= -20283 && $asc <= -19776) return &#39;B&#39;;  
    if ($asc >= -19775 && $asc <= -19219) return &#39;C&#39;;  
    if ($asc >= -19218 && $asc <= -18711) return &#39;D&#39;;  
    if ($asc >= -18710 && $asc <= -18527) return &#39;E&#39;;  
    if ($asc >= -18526 && $asc <= -18240) return &#39;F&#39;;  
    if ($asc >= -18239 && $asc <= -17923) return &#39;G&#39;;  
    if ($asc >= -17922 && $asc <= -17418) return &#39;H&#39;;  
    if ($asc >= -17417 && $asc <= -16475) return &#39;J&#39;;  
    if ($asc >= -16474 && $asc <= -16213) return &#39;K&#39;;  
    if ($asc >= -16212 && $asc <= -15641) return &#39;L&#39;;  
    if ($asc >= -15640 && $asc <= -15166) return &#39;M&#39;;  
    if ($asc >= -15165 && $asc <= -14923) return &#39;N&#39;;  
    if ($asc >= -14922 && $asc <= -14915) return &#39;O&#39;;  
    if ($asc >= -14914 && $asc <= -14631) return &#39;P&#39;;  
    if ($asc >= -14630 && $asc <= -14150) return &#39;Q&#39;;  
    if ($asc >= -14149 && $asc <= -14091) return &#39;R&#39;;  
    if ($asc >= -14090 && $asc <= -13319) return &#39;S&#39;;  
    if ($asc >= -13318 && $asc <= -12839) return &#39;T&#39;;  
    if ($asc >= -12838 && $asc <= -12557) return &#39;W&#39;;  
    if ($asc >= -12556 && $asc <= -11848) return &#39;X&#39;;  
    if ($asc >= -11847 && $asc <= -11056) return &#39;Y&#39;;  
    if ($asc >= -11055 && $asc <= -10247) return &#39;Z&#39;;  
    return null;  
}  
  
echo getFirstCharter(&#39;为&#39;);  
  
?>