如何解决DioError [DioErrorType.DEFAULT]:将对象转换为可编码对象失败:Flutter 中“FormData”的实例
我想使用 Dio 包将我的图像上传到服务器。我在 Dio 文档中看到使用表单数据上传文件如下所示:
var formData = FormData.fromMap({
'name': 'wendux','age': 25,'file': await MultipartFile.fromFile('./text.txt',filename: 'upload.txt')
});
response = await dio.post('/info',data: formData);
在那之后,我有一个函数可以将图像发送到 API。这是我的功能:
Future<CommonResponse> submitDocumentSpaj(SubmitDocumentRequest data) async {
final fileName = data.file.path.split('/').last;
final formData = FormData.fromMap({
'multipartFile':
await MultipartFile.fromFile(data.file.path,filename: fileName),'path_id': 9,'subFolder': '${data.subFolder}','lus_id': 1,'username': '${data.username}','type': data.loginType,'filename': '$fileName','no_temp': data.noTemp,'last_index': data.lastFile,});
print('multipartFile --> ${data.file.path}');
print('path_id --> 9');
print('subFolder --> ${data.subFolder}');
print('lus_id --> 1');
print('username --> ${data.username}');
print('type --> ${data.loginType}');
print('filename --> $fileName');
print('no_temp --> ${data.noTemp}');
print('last_index --> ${data.lastFile}');
final response = await dio.post(
'my_url',data: formData,options: Options(
contentType:
'multipart/form-data; boundary=<calculated when request is sent>',receiveTimeout: 60000,sendTimeout: 60000,),);
return CommonResponse.fromJson(response.data);
}
我检查数据不为空,但出现如下错误:
flutter: Dio Response Error --> DioError [DioErrorType.DEFAULT]: Converting object to an encodable object failed: Instance of 'FormData'
flutter: #0 _JsonStringifier.writeObject (dart:convert/json.dart:687:7)
flutter: #1 _JsonStringStringifier.printOn (dart:convert/json.dart:876:17)
flutter: #2 _JsonStringStringifier.stringify (dart:convert/json.dart:861:5)
flutter: #3 JsonEncoder.convert (dart:convert/json.dart:261:30)
flutter: #4 JsonCodec.encode (dart:convert/json.dart:171:45)
flutter: #5 jsonEncode (dart:convert/json.dart:81:10)
flutter: #6 LoggingInterceptors.onResponse (package:core/network/logging_interceptors.dart:36:12)
flutter: #7 DioMixin._request._interceptorWrapper.<anonymous closure>.<anonymous closure>.<anonymous closure> (package:dio/src/dio.dart:849:37)
flutter: #8 DioMixin.checkIfNeedEnqueue (package:dio/src/dio.dart:1121:22)
flutter: #9 DioMixin._request._interceptorWrapper.<anonymous closure>.<anonymous closure> (package:dio/src/dio.dart:846:22)
flutter: #10 new Future.<anonymous closure> (dart:async/future.dart:175:37)
flutter: #11 _rootRun (dart:async/zone.dart:1182:47)
flutter: #12 _CustomZone.run (dart:async/zone.dart:1093:19)
flutter: #13 _CustomZone.runGuarded (dart:async/zone.dart:997:7)
flutter: #14 _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1037:23)
flutter: #15 _rootRun (dart:async/zone.dart:1190:13)
flutter: #16 _CustomZone.run (dart:async/zone.dart:1093:19)
flutter: #17 _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:1021:23)
flutter: #18 Timer._createTimer.<anonymous closure> (dart:async-patch/timer_patch.dart:18:15)
flutter: #19 _Timer._runTimers (dart:isolate-patch/timer_impl.dart:397:19)
flutter: #20 _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:428:5)
flutter: #21 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)
我已经在 google 和 StackOverflow 中搜索了错误,但仍未修复。谁能知道我为什么必须修复我的错误?因为我相信我的代码与 dio 中的文档相同,但不同之处在于我添加了像我的 API 一样的自定义标头,并且还添加了自定义 RTO。
并且我已经通过 Postman 使用与 Flutter 相同的数据和文件进行了检查,成功上传到服务器,但是 Flutter 出现错误。
解决方法
为了加载图像,我使用 image_picker 包。 这是我的代码:
TextButton(
onPressed: () async {
Dio dio = Dio();
var response;
var multiPartFile = List<MultipartFile>();
multiPartFile.add(MultipartFile.fromFileSync(_image.path,filename: "image.jpg"));
var formData = FormData.fromMap({
"files": multiPartFile,});
response = await dio.post(URI,data: formData);
print('RESPONSE: $response');
},child: Text("POST"),),
您也可以尝试以 base64 格式发送图像:
final pickedFile = await picker.getImage(source: ImageSource.camera,maxHeight: 480,maxWidth: 640);
List<int> imageBytes = await pickedFile.readAsBytes();
String base64Image = base64Encode(imageBytes);
Dio dio = Dio();
var response;
var formData = FormData.fromMap({
"image": '$base64Image',});
response = await dio.post(URI,data: formData);
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。