ifModifiedSince property

@override DateTime? get ifModifiedSince

The date and time specified by the ifModifiedSinceHeader header, if any.

Implementation

@override
DateTime? get ifModifiedSince {
  List<String>? values = _headers[HttpHeaders.ifModifiedSinceHeader];
  if (values != null) {
    assert(values.isNotEmpty);
    try {
      return HttpDate.parse(values[0]);
    } on Exception {
      return null;
    }
  }
  return null;
}

@override set ifModifiedSince (DateTime? ifModifiedSince)

The date and time specified by the ifModifiedSinceHeader header, if any.

Implementation

@override
set ifModifiedSince(DateTime? ifModifiedSince) {
  _checkMutable();
  if (ifModifiedSince == null) {
    _headers.remove(HttpHeaders.ifModifiedSinceHeader);
  } else {
    // Format "ifModifiedSince" header with date in Greenwich Mean Time (GMT).
    String formatted = HttpDate.format(ifModifiedSince.toUtc());
    _set(HttpHeaders.ifModifiedSinceHeader, formatted);
  }
}