unyx / utils

     * @param   string|null $encoding   The encoding to use.

     * @return  string                  The converted string.

     */

    public static function lowerFirst(string $str, string $encoding = null) : string

    {

        $encoding = $encoding ?: utils\Str::encoding($str);

        // Lowercase the first character and append the remainder.

        return mb_strtolower(mb_substr($str, 0, 1, $encoding), $encoding) . mb_substr($str, 1, null, $encoding);

    }

    /**

     * Converts the string to "snake_case" using whitespace, dashes and underscores as case delimiters (all of

     * @param   string|null $encoding   The encoding to use.

     * @return  string                  The converted string.

     */

    public static function upperFirst(string $str, string $encoding = null) : string

    {

        $encoding = $encoding ?: utils\Str::encoding($str);

        // Uppercase the first character and append the remainder.

        return mb_strtoupper(mb_substr($str, 0, 1, $encoding), $encoding) . mb_substr($str, 1, null, $encoding);

    }

}