Form/Type/DatetimeType.php
public static function convertMalotToIntlFormater($formatter)
    {
        $malotToIntl = array_combine(self::$malotFormater, self::$intlFormater);

        $patterns = preg_split('([\\\/.:_;,\s-\ ]{1})', $formatter);
        $exits = array();

        foreach ($patterns as $val) {
            if (isset($malotToIntl[$val])){
                $exits[$val] = $malotToIntl[$val];
            } else {
                // it can throw an Exception
                $exits[$val] = $val;
            }
        }

        return str_replace(array_keys($exits), array_values($exits), $formatter);
    }
public static function convertMalotToIntlFormater($formatter)
    {
        $malotToIntl = array_combine(self::$malotFormater, self::$intlFormater);

        $patterns = preg_split('([\\\/.:_;,\s-\ ]{1})', $formatter);
        $exits = array();

        foreach ($patterns as $val) {
            if (isset($malotToIntl[$val])){
                $exits[$val] = $malotToIntl[$val];
            } else {
                // it can throw an Exception
                $exits[$val] = $val;
            }
        }

        return str_replace(array_keys($exits), array_values($exits), $formatter);
    }
Convert the Bootstrap Datetimepicker date format to PHP date format