function Unicode::truncateBytes

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 $string: The string to truncate.

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

Return value

string The truncated string.

1 call to Unicode::truncateBytes()

ExceptionHandler::handleExecutionException in core/modules/mysql/src/Driver/Database/mysql/ExceptionHandler.php

Handles exceptions thrown during execution of statement objects.

File

core/lib/Drupal/Component/Utility/Unicode.php, line 209

Class

Unicode

Provides Unicode-related conversions and operations.

Namespace

Drupal\Component\Utility

Code

public static function truncateBytes($string, $len) {
    if (strlen($string) <= $len) {
        return $string;
    }
    if (ord($string[$len]) < 0x80 || ord($string[$len]) >= 0xc0) {
        return substr($string, 0, $len);
    }
    // Scan backwards to beginning of the byte sequence.
    // @todo Make the code more readable in https://www.drupal.org/node/2911497.
    while (--$len >= 0 && ord($string[$len]) >= 0x80 && ord($string[$len]) < 0xc0) {
    }
    return substr($string, 0, $len);
}