How to get file stream value from "file_picker" flutter web? - flutter

Question

I need to pick an image from gallery and also have an another field for drag image.
For drag and drop field I used flutter_dropzone.
and used getFileStream(event) data to upload data into server.But file_picker: ^5.2.4 is used to pick image from gallery.So how to get filestream data from this package.
I got bytes but that is not working I needed filestream value
Code using file_picker
void chooseImage() async {
pickedFile = await FilePicker.platform.pickFiles(
type: FileType.custom,
withReadStream: true,
allowedExtensions: [
'jpg','jpeg','png'
]
);
if (pickedFile != null) {
try {
base64 = pickedFile!.files.first.bytes;
base64String.value=base64.toString();
String mime = pickedFile!.files.first.extension.toString();
getS3url("image/$mime" ,base64String.value,from: "cameraIcon");
//withReadStream
//getFileStream(event);
} catch (err) {
print(err);
}
} else {
}
}

Answer 1

Copied from https://github.com/miguelpruivo/flutter_file_picker/wiki/FAQ
import 'package:file_picker/file_picker.dart';
import 'package:http/http.dart' as http;
import 'package:http_parser/http_parser.dart';
import 'package:mime/mime.dart';
void main() async {
final result = await FilePicker.platform.pickFiles(
type: FileType.custom,
allowedExtensions: [
'jpg',
'png',
'mp4',
'webm',
],
withData: false,
withReadStream: true,
);
if (result == null || result.files.isEmpty) {
throw Exception('No files picked or file picker was canceled');
}
final file = result.files.first;
final filePath = file.path;
final mimeType = filePath != null ? lookupMimeType(filePath) : null;
final contentType = mimeType != null ? MediaType.parse(mimeType) : null;
final fileReadStream = file.readStream;
if (fileReadStream == null) {
throw Exception('Cannot read file from null stream');
}
final stream = http.ByteStream(fileReadStream);
final uri = Uri.https('siasky.net', '/skynet/skyfile');
final request = http.MultipartRequest('POST', uri);
final multipartFile = http.MultipartFile(
'file',
stream,
file.size,
filename: file.name,
contentType: contentType,
);
request.files.add(multipartFile);
final httpClient = http.Client();
final response = await httpClient.send(request);
if (response.statusCode != 200) {
throw Exception('HTTP ${response.statusCode}');
}
final body = await response.stream.transform(utf8.decoder).join();
print(body);
}