_mb_strlen() WP 4.2.0
Internal compat function to mimic mb_strlen().
Only understands UTF-8 and 8bit. All other character sets will be treated as 8bit. For $encoding === UTF-8, the $str input is expected to be a valid UTF-8 byte sequence. The behavior of this function for invalid inputs is undefined.
Эта функция считается внутренней для использования самим ядром. Не рекомендуется использовать эту функцию в своем коде.
Хуков нет.
Возвращает
Число
. String length of $str.
Использование
_mb_strlen( $str, $encoding );
- $str(строка) (обязательный)
- The string to retrieve the character length from.
- $encoding(строка/null)
- Character encoding to use.
По умолчанию: null
Список изменений
С версии 4.2.0 | Введена. |
Код _mb_strlen() mb strlen WP 5.7
function _mb_strlen( $str, $encoding = null ) {
if ( null === $encoding ) {
$encoding = get_option( 'blog_charset' );
}
/*
* The solution below works only for UTF-8, so in case of a different charset
* just use built-in strlen().
*/
if ( ! in_array( $encoding, array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ), true ) ) {
return strlen( $str );
}
if ( _wp_can_use_pcre_u() ) {
// Use the regex unicode support to separate the UTF-8 characters into an array.
preg_match_all( '/./us', $str, $match );
return count( $match[0] );
}
$regex = '/(?:
[\x00-\x7F] # single-byte sequences 0xxxxxxx
| [\xC2-\xDF][\x80-\xBF] # double-byte sequences 110xxxxx 10xxxxxx
| \xE0[\xA0-\xBF][\x80-\xBF] # triple-byte sequences 1110xxxx 10xxxxxx * 2
| [\xE1-\xEC][\x80-\xBF]{2}
| \xED[\x80-\x9F][\x80-\xBF]
| [\xEE-\xEF][\x80-\xBF]{2}
| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences 11110xxx 10xxxxxx * 3
| [\xF1-\xF3][\x80-\xBF]{3}
| \xF4[\x80-\x8F][\x80-\xBF]{2}
)/x';
// Start at 1 instead of 0 since the first thing we do is decrement.
$count = 1;
do {
// We had some string left over from the last round, but we counted it in that last round.
$count--;
/*
* Split by UTF-8 character, limit to 1000 characters (last array element will contain
* the rest of the string).
*/
$pieces = preg_split( $regex, $str, 1000 );
// Increment.
$count += count( $pieces );
// If there's anything left over, repeat the loop.
} while ( $str = array_pop( $pieces ) );
// Fencepost: preg_split() always returns one extra item in the array.
return --$count;
}