文章目录

官方文档：
https://github.com/flutterchina/dio/blob/master/README-ZH.md
由于flutter目前的http请求功能相对比较单一，所以推荐一款flutter中网络请求的三方库，这个也是官方推荐的库，口碑不错，可以研究。

使用Dio的配置

默认配置


  // ①使用默认配置
  Dio dio = new Dio();
  // 配置dio实例
  dio.options.baseUrl = 'https://www.wanandroid.com/';
  dio.options.connectTimeout = 5000;
  dio.options.receiveTimeout = 3000;

通过options配置

//  ②通过传递一个 `options`来创建dio实例
  BaseOptions options = new BaseOptions(
    baseUrl: 'https://www.wanandroid.com/',
    connectTimeout: 5000,
    receiveTimeout: 3000,
  );
  Dio dio = new Dio(options);

GET 请求

//    response = await dio.get('article/list/0/json?cid=60');
//    或者
  response = await dio.get('article/list/0/json', queryParameters: {"cid": 60});
  print(response.data.toString());

POST请求

 response = await dio.post("test", data: {"id": 12, "name": "blissyang"});

多个并发请求:

  response = Future.wait([dio.post('info'), dio.get('token')]) as Response;

下载文件

response = await dio.download('https://www.google.com/', './by.html',
      onReceiveProgress: (int count, int total) {
      //下载文件的进度监听
    print('$count $total');
  });

以流的方式接收响应数据：

 Response<List<int>> rs = await Dio().get<List<int>>(
    url,
    options: Options(responseType: ResponseType.bytes), //设置接收类型为bytes
  );
  print(rs.data);

发送表单请求 FormData:

 FormData formData = new FormData.from({
    "name": "blissyang",
    'age': 25,
  });
  response = await dio.post('info', data: formData);

通过FormData上传多个文件:

 FormData formData1 = new FormData.from({
    'name': 'blissyang',
    'age': 28,
    'file1': new UploadFileInfo(new File('./upload.txt'), 'upload.txt'),
//     支持直接上传字节数组 (List<int>) ，方便直接上传内存中的内容
    'file2':
        new UploadFileInfo.fromBytes(utf8.encode('hello world'), 'word.txt'),
    'files': [
      new UploadFileInfo(new File('./example/upload.txt'), 'upload.txt'),
      new UploadFileInfo(new File('./example/upload.txt'), 'upload.txt'),
    ]
  });
  response = await dio.post('info', data: formData1);

监听发送(上传)数据进度:

  response = await dio.post("http://www.dtworkroom.com/doris/1/2.0.0/test",
      data: {"aa": "bb" * 22}, onSendProgress: (int sent, int total) {
    print('$sent $total');
  });

以流的形式提交二进制数据：

// 二进制数据
  List<int> postData = <int>[];
  await dio.post(
    url,
    data: Stream.fromIterable(postData.map((e) => [e])),//创建一个Stream<List<int>>
    options: Options(
      headers: {
        HttpHeaders.contentLengthHeader:postData.length,// 设置content-length
//        如果要监听提交进度，则必须设置content-length，反之则是可选的。
      }
    )
  );