PHP function to calculate the length of Chinese string and intercept Chinese string

header('Content-type:text/html;charset=utf-8');
/**
* Function to count the length of Chinese strings
* @param $str The string to calculate the length
* @param $type Calculation length type, 0 (default) means one Chinese character is counted as one character, 1 means one Chinese character is counted as two characters
* @http://bbs.it-home.org
*
*/
function abslength($str)
{
if( empty($str)){
return 0;
}
if(function_exists('mb_strlen')){
return mb_strlen($str,'utf-8');
}
else {
preg_match_all("/./ u", $str, $ar);
return count($ar[0]);
}
}
$str = 'Script Academy welcomes everyone, ye! ';
$len = abslength($str);
var_dump($len); //return 12
$len = abslength($str,'1');
echo ''.$len ; //return 22
/*
utf-8 encoding to intercept Chinese strings, the parameters can refer to the substr function
@param $str The string to be intercepted
@param $start The starting position to be intercepted, negative numbers are inverse To intercept
@param $end The length to be intercepted
*/
function utf8_substr($str,$start=0) {
if(empty($str)){
return false;
}
if (function_exists(' mb_substr')){
if(func_num_args() >= 3) {
$end = func_get_arg(2);
return mb_substr($str,$start,$end,'utf-8');
}
else {
mb_internal_encoding("UTF-8");
return mb_substr($str,$start);
}
}
else {
$null = "";
preg_match_all("/./u", $str, $ ar);
if(func_num_args() >= 3) {
$end = func_get_arg(2);
return join($null, array_slice($ar[0],$start,$end));
}
 else {
return join($null, array_slice($ar[0],$start));
}
}
}
$str2 = 'wo wants to intercept zhongwen';
echo '';
echo utf8_substr($str2,0,-4); //return wo want to intercept zhon
?>

2. Support gb2312, gbk, utf-8, big5 Chinese interception method

/*
* Chinese interception, supports gb2312, gbk, utf-8, big5
* bbs.it-home.org
* @param string $str The string to be intercepted
 * @param int $start interception starting position
* @param int $length interception length
* @param string $charset utf-8|gb2312|gbk|big5 encoding
* @param $suffix whether to add a suffix
*/
 public function csubstr($str, $start=0, $length, $charset="utf-8", $suffix=true)
{
if(function_exists("mb_substr"))
{
if(mb_strlen($str , $charset) <= $length) return $str;
$slice = mb_substr($str, $start, $length, $charset);
}
else
{
$re['utf-8'] = "/[x01-x7f]|[xc2-xdf][x80-xbf]|[xe0-xef][x80-xbf]{2}|[xf0-xff][x80-xbf]{3}/";
 $re['gb2312'] = "/[x01-x7f]|[xb0-xf7][xa0-xfe]/";
$re['gbk'] = "/[x01-x7f]|[x81-xfe ][x40-xfe]/";
$re['big5'] = "/[x01-x7f]|[x81-xfe]([x40-x7e]|xa1-xfe])/";
preg_match_all($ re[$charset], $str, $match);
if(count($match[0]) <= $length) return $str;
$slice = join("",array_slice($match[0] , $start, $length));
}
if($suffix) return $slice."…";
return $slice;
}
?>