【PHP】php substr 無法正確切utf-8中文字解決方法

提供者：阿勇學長



function cut_str($string, $sublen, $start = 0, $code = 'UTF-8')

{

if($code == 'UTF-8')

{

$pa = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|\xe0[\xa0-\xbf][\x80-\xbf]|[\xe1-\xef][\x80-\xbf][\x80-\xbf]|\xf0[\x90-\xbf][\x80-\xbf][\x80-\xbf]|[\xf1-\xf7][\x80-\xbf][\x80-\xbf][\x80-\xbf]/";

preg_match_all($pa, $string, $t_string);



if(count($t_string[0]) - $start > $sublen)

return join('', array_slice($t_string[0], $start, $sublen))."..";

return join('', array_slice($t_string[0], $start, $sublen));

}

else

{

$start = $start*2;

$sublen = $sublen*2;

$strlen = strlen($string);

$tmpstr = '';

for($i=0; $i<$strlen; $i++){

if($i>=$start && $i<($start+$sublen))

{

if(ord(substr($string, $i, 1))>129)

$tmpstr.= substr($string, $i, 2);

else

$tmpstr.= substr($string, $i, 1);

}

if(ord(substr($string, $i, 1))>129)

$i++;

}

if(strlen($tmpstr)<$strlen )

$tmpstr.= "..";

return $tmpstr;

}

}