如何在flutter中发布没有字符串编码的图像文件？

import 'dart:typed_data';
import 'package:flutter/services.dart';

Future<Uint8List> getImageBytes() async {
  String imageUrl = 'https://example.com/image.jpg';
  NetworkImage image = NetworkImage(imageUrl);
  ByteData byteData = await image.obtainKey(const ImageConfiguration()).then(
      (key) => key.bundle.load(key.name));
  Uint8List imageBytes = byteData.buffer.asUint8List();
  return imageBytes;
}

dependencies:
  flutter:
    sdk: flutter
  path_provider: ^2.0.7

import 'dart:io';
import 'package:path_provider/path_provider.dart';

Future<File> saveImageToFile(Uint8List imageBytes) async {
  Directory directory = await getTemporaryDirectory();
  File file = File('${directory.path}/image.jpg');
  await file.writeAsBytes(imageBytes);
  return file;
}

dependencies:
  flutter:
    sdk: flutter
  image_picker: ^0.8.4+4

import 'package:image_picker/image_picker.dart';

Future<void> pickAndPublishImage() async {
  File imageFile = await ImagePicker().pickImage(source: ImageSource.gallery);
  if (imageFile != null) {
    // 处理图像文件
  }
}