Truncate a string to first n characters of a string and add three dots if any characters are removed

How can I get the first n characters of a string in PHP? What's the fastest way to trim a string to a specific number of characters, and append '...' if needed?

To truncate the string after a set number of characters:

<?php

/**
 * @param string      $text          The text to shorten.
 * @param int         $limit         Max characters **including** the suffix. Must be ≥ 1.
 * @param string      $suffix        What to append when truncated (default: ellipsis).
 * @param bool        $preserveWords Try not to cut a word in half.
 * @param string|null $encoding      Explicit multibyte encoding (null = mb_internal_encoding()).
 *
 * @throws InvalidArgumentException  If $limit is less than 1.
 */
function truncate(
    string $text,
    int $limit = 100,
    string $suffix = '…',
    bool $preserveWords = true,
    ?string $encoding = null
): string {
    if ($limit < 1) {
        throw new InvalidArgumentException('$limit must be at least 1');
    }

    $encoding ??= mb_internal_encoding();
    $suffixLen = mb_strlen($suffix, $encoding);

    if ($suffixLen >= $limit) {
        return mb_substr($suffix, 0, $limit, $encoding);
    }

    if (mb_strlen($text, $encoding) <= $limit) {
        return $text;
    }

    $cut = $limit - $suffixLen;
    $snippet = mb_substr($text, 0, $cut, $encoding);

    if ($preserveWords) {
        $result = preg_replace('/\s+\S*$/u', '', $snippet);
        
        // If preg_replace fails, $snippet remains unchanged
        if (is_string($result)) {
             $snippet = $result;
        }
    }

    return rtrim($snippet) . $suffix;
}

Note: This function uses the Multibyte String functions in PHP so ensure the mbstring extension is enabled.