如何在颤动中从 HttpClientResponse 返回响应答案

【问题标题】：How to return response from HttpClientResponse in flutter如何在颤动中从 HttpClientResponse 返回响应
【发布时间】：2021-04-16 18:07:16
【问题描述】：

我在 Flutter 中使用 HttpClient 从我的 API 获取数据，这是我的函数

我正在尝试从响应函数返回值。

    Future<String> SendOTPtoVerify(
    {String endpoint, String number, String OTP}) async {
  try {
    var client = new HttpClient();
    client.badCertificateCallback =
        ((X509Certificate cert, String host, int port) => true);
    Map valueMap;
    await client.postUrl(Uri.parse(endpoint)).then((HttpClientRequest request) {
      String body = '{"mobileNumber": "$number","code": "$OTP"}';
      request.contentLength = body.length;
      request.headers.contentType =
          new ContentType("application", "json", charset: "utf-8");
      request.write(body);
      return request.close();
    }).then((HttpClientResponse response) {
      response.transform(utf8.decoder).listen((event) {
        valueMap = json.decode(event);
     // this print works fine and prints the desired result 
        print("this is the event $event");
      });
      // I added this return in order to get the event as variable
      return event;
    });
   
  } catch (e) {
    print('Error: $e');
  }
}

函数SendOTPtoVerify 工作正常，API 向我发送响应，但我只能打印它，我想要返回它，以便在其他类中使用它。这是我在其他课程中的代码，但即使我在 FutureBuilder 小部件中使用它也不会返回任何内容

                 PinFieldAutoFill(
                        codeLength: 6,
                        onCodeChanged: (val){
                        if(val.length == 6 ) {
                          FutureBuilder(
                              future: SendOTPtoVerify(number: widget.full_number,
                                  endpoint: "https://my_api.servehttp.com:3000/api/codeValidation",
                                  OTP: val),
                              builder: ( BuildContext context , AsyncSnapshot snapshot){
                               // this print show nothing when I run the app 
                                print("this is the builder");
                               // even this container is not returned
                                return Container(child: Text(snapshot.data),);
                                  },
                               );
                             }
                           },
                         ),

请注意，我必须使用 HttpClient 并且事件打印正确，但我无法返回其值

【问题讨论】：

标签： flutter https flutter-futurebuilder

【解决方案1】：

试试这个方法：

  var headers = {
    "Authorization": user.token,
    "Content-Type": "multipart/form-data; boundary=<calculated when request is sent>",
  };

  var request = MultipartRequest('POST', Api.saveData);

  request.fields.addAll({
    "Model": model.trim(),
    "Brand": brand.trim(),
    "MAC": version.trim(),
    "IMEI": appVersion.trim(),
    "PhoneNumber": (user.phone ?? "").trim(),
  });

  for (var file in files) {
    request.files.add(
      await MultipartFile.fromPath("ListFiles", file.path),
    );
  }

  request.headers.addAll(Map<String, String>.from(headers));

  var response = await request.send();
  String result = await response.stream.bytesToString();
  return response.statusCode;

这里，result 是您希望来自API 的回复。

如果您有任何问题，请随时告诉我。

编码愉快。

【讨论】：