function drupal_truncate_bytes

Truncates a UTF-8-encoded string safely to a number of bytes.

If the end position is in the middle of a UTF-8 sequence, it scans backwards until the beginning of the byte sequence.

Use this function whenever you want to chop off a string at an unsure location. On the other hand, if you're sure that you're splitting on a character boundary (e.g. after using strpos() or similar), you can safely use substr() instead.

Parameters

$string: The string to truncate.

$len: An upper limit on the returned string length.

Return value

The truncated string.

File

includes/unicode.inc, line 274

Code

function drupal_truncate_bytes($string, $len) {
    if (strlen($string) <= $len) {
        return $string;
    }
    if (ord($string[$len]) < 0x80 || ord($string[$len]) >= 0xc0) {
        return substr($string, 0, $len);
    }
    // Scan backwards to beginning of the byte sequence.
    while (--$len >= 0 && ord($string[$len]) >= 0x80 && ord($string[$len]) < 0xc0) {
    }
    return substr($string, 0, $len);
}