addFile method Null safety

Future<PartBuilder> addFile(
  1. File file,
  2. MediaType mediaType,
  3. {ContentDispositionHeader? disposition}
)

Adds the file part asyncronously.

file The file that should be added. mediaType The media type of the file. Specify the optional content disposition element, if it should not be populated automatically. This will add an AttachmentInfo element to the attachments list of this builder.

Implementation

Future<PartBuilder> addFile(File file, MediaType mediaType,
    {ContentDispositionHeader? disposition}) async {
  disposition ??=
      ContentDispositionHeader.from(ContentDisposition.attachment);
  disposition.filename ??= _getFileName(file);
  disposition.size ??= await file.length();
  disposition.modificationDate ??= await file.lastModified();
  final child = addPart(disposition: disposition);
  final data = await file.readAsBytes();
  child.transferEncoding = TransferEncoding.base64;
  final info = AttachmentInfo(file, mediaType, disposition.filename,
      disposition.size, disposition.disposition, data, child);
  attachments.add(info);
  child.setContentType(mediaType, name: disposition.filename);
  child._part.mimeData =
      TextMimeData(MailCodec.base64.encodeData(data), false);
  ;
  return child;
}