fields.py 文件源码

 复制代码def from_native(self, value):
        if value in validators.EMPTY_VALUES:
            return None

        if isinstance(value, datetime.datetime):
            if timezone and settings.USE_TZ and timezone.is_aware(value):
                # Convert aware datetimes to the default time zone
                # before casting them to dates (#17742).
                default_timezone = timezone.get_default_timezone()
                value = timezone.make_naive(value, default_timezone)
            return value.date()
        if isinstance(value, datetime.date):
            return value

        for fmt in self.input_formats:
            if fmt.lower() == ISO_8601:
                try:
                    parsed = parse_date(value)
                except (ValueError, TypeError):
                    pass
                else:
                    if parsed is not None:
                        return parsed
            else:
                try:
                    parsed = datetime.datetime.strptime(value, fmt)
                except (ValueError, TypeError):
                    pass
                else:
                    return parsed.date()

        msg = self.error_messages['invalid'] % readable_date_formats(self.input_formats)

        raise ValidationError(msg)