我正在尝试发送两个图像文件列表,但出现错误,我不知道为什么会发生这种情况 这是我使用的函数:
Future<dynamic> upload(List<File> imageFile, List<File> backID) async {
var headers =
Provider.of<LoginUserProvider>(context, listen: false).httpHeader;
var uri = Uri.parse(
"xyz");
var request = new http.MultipartRequest("POST", uri);
var requestCopy = new http.MultipartRequest("POST", uri);
request.headers.addAll(headers);
//request.headers.addAll(Environment.requestHeaderMedia);
for (int i = 0; i < uploadedFilesList.length; i++) {
var length = await imageFile[i].length();
var stream =
// ignore: deprecated_member_use
new http.ByteStream(DelegatingStream.typed(imageFile[i].openRead()));
var multipartFile = http.MultipartFile(
'back_id_photos[$i]',
stream,
length,
contentType: MediaType('application', 'x-tar'),
);
var multipartFilePhotos = new http.MultipartFile(
'photos[$i]',
stream,
length,
contentType: MediaType('application', 'x-tar'),
);
request.fields['section_id'] = VillaID.toString();
request.fields['start_date'] = requeststartDate;
request.fields['end_date'] = requestendDate;
request.fields['names'] = _nameController.toString();
request.fields['phones'] = _phoneController.toString();
request.fields['photos'] = multipartFilePhotos.toString();
request.fields['back_id_photos'] = multipartFile.toString();
//contentType: new MediaType('image', 'png'));
request.files.add(multipartFile);
request.files.add(multipartFilePhotos);
var response = await request.send();
print(response.statusCode);
response.stream.transform(utf8.decoder).listen((value) {
print(value);
});
var streamedResponse = await requestCopy.send();
var responses = await http.Response.fromStream(streamedResponse);
// ignore: unused_local_variable
final responseData = json.decode(responses.body) as Map<String, dynamic>;
print(json.decode(responses.body));
if (response.statusCode == 200 || response.statusCode == 201) {
return true;
}
}
}
以及部分
var response = await request.send();
我在点 (.) 之前出现了错误,这就是显示的错误
unhandled exception: invalid argument(s) (input): must not be null Can anyone tell me what should i do to solve that !
最佳答案
按如下方式发送您的多部分文件,并使用 await http.Multipart
因为访问文件是异步函数,并且需要 promise 才能运行。
试试这个:
await http.MultipartFile(
'back_id_photos[$i]',
stream,
length,
contentType: MediaType('application', 'x-tar'),
);
或者
request.files.add(new http.MultipartFile.fromBytes('file', await File.fromUri("<path/to/file>").readAsBytes(), contentType: new MediaType('image', 'jpeg')))
关于api - flutter : unhandled exception: invalid argument,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/65202121/