处理异常 HTTP 请求 flutter

Question

我想处理带有一些错误消息的 HTTP 请求抖动，但我在这里遇到了很多错误。我只是根据建议制作的，但它对我不起作用。请任何人帮助我这是我调用 API

的函数

getData(data, apiUrl) async {
    var tempUrl = _url + apiUrl + await _getToken();
    Uri uri = Uri.parse(tempUrl);
    var fullUrl = uri.replace(queryParameters: data);
    var res;
    try {
      var response = await http.get(fullUrl, headers: _setHeaders()).timeout(
          const Duration(seconds: 60));
      print(response.statusCode);
      if (response.statusCode != 200) {
        res = {
          "success": false,
          "status": response.statusCode,
          "message": _returnResponse(response)
        };
      }
      else {
        res = response;
      }
    }
    on SocketException {
      throw FetchDataException('No Internet connection');
    }
    on TimeoutException catch (e) {
      res = {
        "success": false,
        "status": response.statusCode,
        "message": "Connection timeout"
      };
    } on Error catch (e) {
      print('Error: $e');
    }

    return res;
  }

这是我对除 200

以外其他人的 return 回复

dynamic _returnResponse(http.Response response) {
    switch (response.statusCode) {
      case 400:
        throw BadRequestException(response.body.toString());
      case 401:
      case 403:
        throw UnauthorisedException(response.body.toString());
      case 500:
      default:
        throw FetchDataException(
            'Error occured while Communication with Server with StatusCode : ${response
                .statusCode}');
    }
  }

这是我的 app_exception.dart 我从 Whosebug 和其他论坛

class AppException implements Exception {
  final _message;
  final _prefix;

  AppException([this._message, this._prefix]);

  String toString() {
    return "$_prefix$_message";
  }
}

class FetchDataException extends AppException {
  FetchDataException([String message])
      : super(message, "Error During Communication: ");
}

class BadRequestException extends AppException {
  BadRequestException([message]) : super(message, "Invalid Request: ");
}

class UnauthorisedException extends AppException {
  UnauthorisedException([message]) : super(message, "Unauthorised: ");
}

class InvalidInputException extends AppException {
  InvalidInputException([String message]) : super(message, "Invalid Input: ");
}

我尝试了很多建议，但根本没有用

我遇到了这个错误

Error: 'SocketException' isn't a type. on SocketException { ^^^^^^^^^^^^^^^

Error: 'TimeoutException' isn't a type. on TimeoutException catch (e) { ^^^^^^^^^^^^^^^^

Answer 1

我使用了 dio 包。这比我做的更容易，错误更少

https://pub.dev/packages/dio

Answer 2

如果发生的错误是 SocketException 和 Timeout 异常，请确保您已在该文件中分别导入了 dart.io 和 dart.async。关于您的代码，我能够成功运行它，但您可以参考 answer by Paresh Mangukiya for a step by step or refer here 以进一步了解如何在 flutter 中使用自定义错误响应处理网络调用和异常。

处理异常 HTTP 请求 flutter

Handling exception HTTP request flutter

exception

http

httprequest

dart

flutter