android - DioError [DioErrorType.RESPONSE] : Http status error [400] Exception

Question

我正在开发一个 Flutter Restful web 应用程序和 web api 后端作为 asp.net 核心。当我尝试使用发布请求发送表单数据时，它会抛出此错误

DioError [DioErrorType.RESPONSE]: Http status error [400] Exception

代码

onPressed: () async {
 String email_value = emailController.text;
 String password_value = passController.text;
 String fullname_value = fullnameController.text;
 var repassword_value = repassController.text;
 print("$email_value");
 if (password_value == repassword_value) {
 try{
 Dio dio = Dio();
 var body = jsonEncode(
  {
    'FullName': '$fullname_value',
    'Email': '$email_value',
    'Password': '$password_value'
  }
 );
 print("Body" + body);
 Response response = await dio.post("http://iamtv.chainuniverse.com/api/Accounts/Register",
  data: body,
  options: Options(
    contentType: Headers.jsonContentType,
  )
 );
 var jsonData = json.decode(response.data);
 print(jsonData);
 if (response.statusCode > 200 &&
    response.statusCode < 250) {
  print("Sucess");
  await loginAction();
  print("Registered");
 }
 else{
  print(jsonData);
 }

但是当我在不使用 textcontroller Text 的情况下手动发送数据时，它可以工作。请帮我解决这个问题

在 POSTMAN 中完美工作

Answer 1

迟到的答案，可能对你有所帮助。

我遇到了同样的错误 Dio和 form-data .有效!添加后contentType

FormData formData = FormData.fromMap({
  "image-param-name": await MultipartFile.fromFile(
    imageFile.path,
    filename: fileName,
    contentType: new MediaType("image", "jpeg"), //add this
  ),
});

完整代码

var dio = Dio();
String fileName = imageFile.path.split('/').last;
FormData formData = FormData.fromMap({
  "image-param-name": await MultipartFile.fromFile(
    imageFile.path,
    filename: fileName,
    contentType: new MediaType("image", "jpeg"), //add this
  ),
});

var response = await dio.post(
  "url",
  data: formData,
  options: Options(
    headers: {
      "Authorization": auth-token
    },
  ),
  onSendProgress: (int sent, int total) {
    debugPrint("sent${sent.toString()}" + " total${total.toString()}");
  },
).whenComplete(() {
  debugPrint("complete:");
}).catchError((onError) {
  debugPrint("error:${onError.toString()}");
});