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Deserializing a nested JSON string, cannot access properties - c#

I am having issues deserializing a nested JSON array from the Genius lyric website API. I formulated the object using http://json2csharp.com. When I deserialize the object, I am unable to access the properties inside of the class, which wasn't entirely unexpected, I am just not sure how to properly design an actual solution to the problem. The JSON object conversions work fine when they are not nested.
What would be the best way to go about handling this?
Here is the conversion code:
string test = await G.SearchGeniusASync(textBox1.Text);
var data = JsonConvert.DeserializeObject<GeniusApiObject>(test);
Here is my class:
class GeniusApiObject
{
public class Meta
{
public int status { get; set; }
}
public class Stats
{
public bool hot { get; set; }
public int unreviewed_annotations { get; set; }
public int concurrents { get; set; }
public int pageviews { get; set; }
}
public class PrimaryArtist
{
public string api_path { get; set; }
public string header_image_url { get; set; }
public int id { get; set; }
public string image_url { get; set; }
public bool is_meme_verified { get; set; }
public bool is_verified { get; set; }
public string name { get; set; }
public string url { get; set; }
public int iq { get; set; }
}
public class Result
{
public int annotation_count { get; set; }
public string api_path { get; set; }
public string full_title { get; set; }
public string header_image_thumbnail_url { get; set; }
public string header_image_url { get; set; }
public int id { get; set; }
public int lyrics_owner_id { get; set; }
public string lyrics_state { get; set; }
public string path { get; set; }
public int? pyongs_count { get; set; }
public string song_art_image_thumbnail_url { get; set; }
public Stats stats { get; set; }
public string title { get; set; }
public string title_with_featured { get; set; }
public string url { get; set; }
public PrimaryArtist primary_artist { get; set; }
}
public class Hit
{
public List<object> highlights { get; set; }
public string index { get; set; }
public string type { get; set; }
public Result result { get; set; }
}
public class Response
{
public List<Hit> hits { get; set; }
}
public class RootObject
{
public Meta meta { get; set; }
public Response response { get; set; }
}
}
This is the source for the SearchGeniusASync method in case it is helpful:
public async Task<string>SearchGeniusASync(string searchParameter)
{
httpClient.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", clientAccessToken);
var result = await httpClient.GetAsync(new Uri("https://api.genius.com/search?q=" + searchParameter), HttpCompletionOption.ResponseContentRead);
var data = await result.Content.ReadAsStringAsync();
return data;
}
This is the scope I am given access to:
https://i.imgur.com/9mZMvfp.png
Here's a sample JSON request in plaintext:
https://pastebin.com/iA8dQafW

GeniusApiObject is not needed in the code, but I'll leave it in just because it helps organize things (may be that something else also has a RootObject from the auto-generator).
The problem is that you are trying to deserialize to what is just an empty class, the class itself has no properties, so you can't deserialize to it. You need to deserialize to the GeniusApiObject.RootObject.
var data = JsonConvert.DeserializeObject<GeniusApiObject.RootObject>(test);
Will deserialize to the .RootObject subclass. This is verified working:
Where I'm using File.ReadAllText("test.json") to load the example API data provided.
Here is a .NET Fiddle showing it working (without the root object and only one song in the response). Thanks to #maccttura.

Related

I've read and reread articles online on how to do this, but it's probably something simple. I'm trying to learn how to process a json response from an API call. I have a simple method I call from Main()
public async void apiTestCall()
{
var httpCall = new HttpClient();
var uri = new Uri("https://api.nasa.gov/mars-photos/api/v1/rovers/curiosity/photos?sol=1000&page=2&api_key=DEMO_KEY");
var result = new DataModel();
var response = await httpCall.GetStringAsync(uri);
result = JsonSerializer.Deserialize<DataModel>(response);
I am expecting "result" to be a DataModel object with the data populated. Right now, there is nothing.
Here is the DataModel class
using System.Collections.Generic;
namespace APITestProject
{
class DataModel
{
public class Camera
{
public int id { get; set; }
public string name { get; set; }
public int rover_id { get; set; }
public string full_name { get; set; }
}
public class Rover
{
public int id { get; set; }
public string name { get; set; }
public string landing_date { get; set; }
public string launch_date { get; set; }
public string status { get; set; }
}
public class Photo
{
public int id { get; set; }
public int sol { get; set; }
public Camera camera { get; set; }
public string img_src { get; set; }
public string earth_date { get; set; }
public Rover rover { get; set; }
}
public class Example
{
public IList<Photo> photos { get; set; }
}
}
}
Any suggestions would be greatly appreciated.
Edit #1: Here is the first 3 entries in the json. I didn't want to post the whole thing but the URL is valid for anyone to run and see the response.
{"photos":[{"id":424926,"sol":1000,"camera":{"id":22,"name":"MAST","rover_id":5,"full_name":"Mast Camera"},"img_src":"http://mars.jpl.nasa.gov/msl-raw-images/msss/01000/mcam/1000ML0044631200305217E01_DXXX.jpg","earth_date":"2015-05-30","rover":{"id":5,"name":"Curiosity","landing_date":"2012-08-06","launch_date":"2011-11-26","status":"active"}},{"id":424927,"sol":1000,"camera":{"id":22,"name":"MAST","rover_id":5,"full_name":"Mast Camera"},"img_src":"http://mars.jpl.nasa.gov/msl-raw-images/msss/01000/mcam/1000MR0044631190503679E04_DXXX.jpg","earth_date":"2015-05-30","rover":
Edit #2: I made some changes based on the comments so far and I used the Paste > Special > JSON as Classes and removed the "wrapper" class. Now I get the populated object. FYI, here is the new class VS generated:
namespace APITestProject
{
public class DataModel
{
public Photo[] photos { get; set; }
}
public class Photo
{
public int id { get; set; }
public int sol { get; set; }
public Camera camera { get; set; }
public string img_src { get; set; }
public string earth_date { get; set; }
public Rover rover { get; set; }
}
public class Camera
{
public int id { get; set; }
public string name { get; set; }
public int rover_id { get; set; }
public string full_name { get; set; }
}
public class Rover
{
public int id { get; set; }
public string name { get; set; }
public string landing_date { get; set; }
public string launch_date { get; set; }
public string status { get; set; }
}
}

Can you try the following amendment
var result = JsonSerializer.Deserialize<DataModel.Example>(response);
as it looks like DataModel.Example is actually the class that you are trying to deserialize to based on the response that comes from the following call -
https://api.nasa.gov/mars-photos/api/v1/rovers/curiosity/photos?sol=1000&page=2&api_key=DEMO_KEY
i.e. It returns an object containing an array of photo objects as you have defined them. As someone else mentioned, no need to encapsulate all of these classes within another class.

You class DataModel just defines other classes, but do not instance them.
According to the data inside the response, you DataModel class should have at least Photos member. It could be type of List<Photo>
class DataModel {
...
public List<Photo> Photos { get; set; }
}
The Photos definition says, that there is some list of photos of Photo type to be expected.

I am trying to deserialize a json (using Newtonsoft.Json), i created the classes, but in json code there is a variable that i don't know if it is corrected or i don't know how to deserialize.
I am getting a null exception on line : MessageBox.Show(root.matriculations._14000.name)
private void btnImportaDados_Click(object sender, EventArgs e)
{
string getDataUrl = "https://xxx.xxx.com/api/matriculations/get.json?entity_code=14000";
try
{
using (var webClient = new System.Net.WebClient())
{
var json = webClient.DownloadString(getDataUrl);
var root = JsonConvert.DeserializeObject<Rootobject>(json);
MessageBox.Show(root.matriculations._14000.name);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
public class Rootobject
{
public Matriculations matriculations { get; set; }
}
public class Matriculations
{
public _14000 _14000 { get; set; }
}
public class _14000
{
public string entity_code { get; set; }
public string name { get; set; }
public string street { get; set; }
public string local { get; set; }
public string postal_code { get; set; }
public string sub_postal_code { get; set; }
public string phone1 { get; set; }
public object phone2 { get; set; }
public string email1 { get; set; }
public object email2 { get; set; }
public string entity_code_2 { get; set; }
public string courseaction_ref { get; set; }
public string courseaction_id { get; set; }
public string course_code { get; set; }
public string course { get; set; }
public Billingorderplan[] billingorderplans { get; set; }
}
public class Billingorderplan
{
public string id { get; set; }
public string paid { get; set; }
public string date { get; set; }
public object obs { get; set; }
public object payment_doc_num { get; set; }
public string value { get; set; }
public string description { get; set; }
public string entity_code { get; set; }
public object paid_date { get; set; }
}
The result(json data) from the url is:
{"matriculations":{"14000":{"entity_code":"14000","name":"Fabio Danilson Sivone Antonio","street":"Rua Dr. Pereira Jardim, Bl. 3 - 25 - 4 B","local":"Luanda","postal_code":"2685","sub_postal_code":"093","phone1":"923810539","phone2":null,"email1":"fabiodanilson1#hotmail.com","email2":null,"entity_code_2":"9957","courseaction_ref":"EPCE_01","courseaction_id":"1828","course_code":"EPCE","course":"Especializa\u00e7\u00e3o Avan\u00e7ada em Investiga\u00e7\u00e3o de Crime Econ\u00f3mico [E-learning]","billingorderplans":[{"id":"298","paid":"0","date":"2020-05-06","obs":null,"payment_doc_num":null,"value":"0.00","description":"Inscri\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"299","paid":"0","date":"2019-11-21","obs":null,"payment_doc_num":null,"value":"0.00","description":"1\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"300","paid":"0","date":"2019-12-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"2\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"301","paid":"0","date":"2020-01-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"3\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"302","paid":"0","date":"2020-02-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"4\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"303","paid":"0","date":"2020-03-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"5\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"304","paid":"0","date":"2020-04-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"6\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"305","paid":"0","date":"2020-05-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"7\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"306","paid":"0","date":"2020-06-08","obs":null,"payment_doc_num":null,"value":"0.00","description":"8\u00aa presta\u00e7\u00e3o","entity_code":"14000","paid_date":null},{"id":"16595","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"20.00","description":"EExt - Atividade","entity_code":"14000","paid_date":null},{"id":"16596","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"45.00","description":"EExt - Teste","entity_code":"14000","paid_date":null},{"id":"16597","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"20.00","description":"EExt - Atividade","entity_code":"14000","paid_date":null},{"id":"16598","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"45.00","description":"EExt - Teste","entity_code":"14000","paid_date":null},{"id":"16599","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"20.00","description":"EExt - Atividade","entity_code":"14000","paid_date":null},{"id":"16601","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"45.00","description":"EExt - Teste","entity_code":"14000","paid_date":null},{"id":"16600","paid":"0","date":"2020-08-27","obs":null,"payment_doc_num":null,"value":"20.00","description":"EExt - Atividade","entity_code":"14000","paid_date":null}]}}}
But that "14000" is a varible value depending from the parameter passed.
How can i do it?
Thank You.

Since 14000 cannot be a variable name you will have to resort to some manual intervention to capture that dynamic value. The cleanest way is to remove the Matriculations class and replace it with Dictionary<int, _14000> (or Dictionary<string, _14000>).
public class Rootobject
{
public Dictionary<int, _14000> matriculations { get; set; }
}
This will ensure that the key is captured correctly even if it is a number. You can read the object from the dictionary's values as such: root.matriculations.Values.First().name. (Remember to import System.Linq for using .First().)
For clarity you can rename _14000 to something more descriptive.

You do not have _14000 in returned JSON but 14000 under matriculations.

This question already has answers here:
How can I deserialize JSON with C#?
(19 answers)
Closed 5 years ago.
I am trying to parse JSON response using newtownsoft.json trying to parse the followers count and writeline.
This is the code:
using Newtonsoft.Json;
using System;
using System.IO;
using System.Net;
namespace J2C
{
class Checker
{
static void Main(string[] args)
{
var client = new WebClient();
var text = client.DownloadString("https://www.instagram.com/2saleapp/?__a=1");
User userObject = JsonConvert.DeserializeObject<User>(text);
Console.WriteLine("Followers count =" + userObject.followed_by);
Console.ReadKey();
}
}
}
and this is the API response:
{
"user": {
"biography": "Install 2Sale app to post your AD instantly!\nSnap, post, and sell. Its time to sale.",
"blocked_by_viewer": false,
"country_block": false,
"external_url": "http://autoigs.com/2sale_install",
"external_url_linkshimmed": "http://l.instagram.com/?u=http%3A%2F%2Fautoigs.com%2F2sale_install&e=ATMoKdz87_iz044M0ebrfU95WQT7JqBpnlGiGH9UDOsn7dRax7G6ZMxjh7wMuHY",
"followed_by": {
"count": 6511
},
"followed_by_viewer": false,
"follows": {
"count": 19
},
I just want to WriteLine Followed_by count numbers.
Any one can help me?
thank you

Copy the raw json to the clipboard. In Visual Studio menu select Edit > Paste Special > Paste JSON As Classes (this item is present at least since version VS2015. For earlier versions see). This will generate a set of classes.
public class Rootobject
{
public User user { get; set; }
public string logging_page_id { get; set; }
}
public class User
{
public string biography { get; set; }
public bool blocked_by_viewer { get; set; }
public bool country_block { get; set; }
public string external_url { get; set; }
public string external_url_linkshimmed { get; set; }
public Followed_By followed_by { get; set; }
public bool followed_by_viewer { get; set; }
public Follows follows { get; set; }
public bool follows_viewer { get; set; }
public string full_name { get; set; }
public bool has_blocked_viewer { get; set; }
public bool has_requested_viewer { get; set; }
public string id { get; set; }
public bool is_private { get; set; }
public bool is_verified { get; set; }
public string profile_pic_url { get; set; }
public string profile_pic_url_hd { get; set; }
public bool requested_by_viewer { get; set; }
public string username { get; set; }
public object connected_fb_page { get; set; }
public Media media { get; set; }
}
public class Followed_By
{
public int count { get; set; }
}
public class Follows
{
public int count { get; set; }
}
public class Media
{
public Node[] nodes { get; set; }
public int count { get; set; }
public Page_Info page_info { get; set; }
}
public class Page_Info
{
public bool has_next_page { get; set; }
public string end_cursor { get; set; }
}
public class Node
{
public string __typename { get; set; }
public string id { get; set; }
public bool comments_disabled { get; set; }
public Dimensions dimensions { get; set; }
public object gating_info { get; set; }
public string media_preview { get; set; }
public Owner owner { get; set; }
public string thumbnail_src { get; set; }
public object[] thumbnail_resources { get; set; }
public bool is_video { get; set; }
public string code { get; set; }
public int date { get; set; }
public string display_src { get; set; }
public string caption { get; set; }
public Comments comments { get; set; }
public Likes likes { get; set; }
public int video_views { get; set; }
}
public class Dimensions
{
public int height { get; set; }
public int width { get; set; }
}
public class Owner
{
public string id { get; set; }
}
public class Comments
{
public int count { get; set; }
}
public class Likes
{
public int count { get; set; }
}
Next, use the Rootobject. It's supposed to work.
var client = new WebClient();
var text = client.DownloadString("https://www.instagram.com/2saleapp/?__a=1");
Rootobject rootObject = JsonConvert.DeserializeObject<Rootobject>(text);
Console.WriteLine("Followers count =" + rootObject.user.followed_by.count);
In general, you should change the naming to conform to the generally accepted naming rules. You should use the JsonProperty attribute.
public class Rootobject
{
[JsonProperty("user")]
public User User { get; set; }
[JsonProperty("logging_page_id")]
public string LoggingPageId { get; set; }
}
And so on.

Create a class with name User in order to deserialize json string to User.
public class User
{
public string biography { get; set; }
public bool blocked_by_viewer { get; set; }
public bool country_block { get; set; }
public string external_url { get; set; }
public string external_url_linkshimmed { get; set; }
public FollowedBy followed_by { get; set; }
public string followed_by_viewer { get; set; }
public Follow follows { get; set; }
}
public class FollowedBy
{
public int count { get; set; }
}
public class Follow
{
public int count { get; set; }
}
After getting json string result using the below line for DeserializeObject to User and then assign it to new User object , after that use userObject for showing result.
User userObject = JsonConvert.DeserializeObject<User>(jsonString);
Now you have a user object that fill property with the API response.

I'm new to JSON.NET, and I've been playing with the new Marvel API that was recently released.
When I call this API it will return the following JSON Data Structure:-
{
"code": 200,
"status": "Ok",
"etag": "f0fbae65eb2f8f28bdeea0a29be8749a4e67acb3",
"data":
{
"offset": 0,
"limit": 20,
"total": 30920,
"count": 20,
"results": [{array of objects}}]
}
}
I can create Classes for this Data like this :
public class Rootobject
{
public int code { get; set; }
public string status { get; set; }
public string etag { get; set; }
public Data data { get; set; }
}
public class Data
{
public int offset { get; set; }
public int limit { get; set; }
public int total { get; set; }
public int count { get; set; }
public Result[] results { get; set; }
}
public class Result
{
}
Now, my issue. The Results that come back from the API can relate to different Objects, it could be results relating to Characters, Comics, Series etc. The objects all hold different properties.
I need to be able to swap out the Result Class properties based on the Entity Type that the results relate too?
Can this actually be done?

You can use var jObj = JObject.Parse(jsonString) then discover what object type it is by which properties are available on the object.
jObj["someComicSpecificProperty"] != null
However this is not full proof and will need to be done on a per object basis for the results array.
An alternate approach I have seen people use is to have a property on the object that is "typeName".
However the root cause of this problem is that you are trying to strongly type a property that is not strongly typed. I would really recommend splitting these different types of results out into different properties so that you don't have this problem.

As promised, I've posted the anser to this problem. It turns out that the JSON response has nested data covering all related data-types, very much like a relational database.
I found something really cool, I basically made a request to the API and converted its response to a string. I then used the debugger to take a copy of the contents to the clipboard.
I created a new Class and Called it MarvelResponse.
I added the NewtonSoft.Json directive to the file, and used the Paste Special option from Edit Menu in VS2012. Here you can paste the option "Paste as JSON CLasses".
After some minor tweaking here is what it provided :-
namespace Kaiser.Training.Data.JSONClasses
{
public class MarvelResponse
{
public int code { get; set; }
public string status { get; set; }
public string etag { get; set; }
public Data data { get; set; }
}
public class Data
{
public int offset { get; set; }
public int limit { get; set; }
public int total { get; set; }
public int count { get; set; }
public Result[] results { get; set; }
}
public class Result
{
public int id { get; set; }
public string name { get; set; }
public string description { get; set; }
public DateTime modified { get; set; }
public Thumbnail thumbnail { get; set; }
public string resourceURI { get; set; }
public Comics comics { get; set; }
public Series series { get; set; }
public Stories stories { get; set; }
public Events events { get; set; }
public Url[] urls { get; set; }
}
public class Thumbnail
{
public string path { get; set; }
public string extension { get; set; }
}
public class Comics
{
public int available { get; set; }
public string collectionURI { get; set; }
public ComicResourceUriItem[] items { get; set; }
public int returned { get; set; }
}
public class ComicResourceUriItem
{
public string resourceURI { get; set; }
public string name { get; set; }
}
public class Series
{
public int available { get; set; }
public string collectionURI { get; set; }
public SeriesResourceItem[] items { get; set; }
public int returned { get; set; }
}
public class SeriesResourceItem
{
public string resourceURI { get; set; }
public string name { get; set; }
}
public class Stories
{
public int available { get; set; }
public string collectionURI { get; set; }
public StoriesResourceItem[] items { get; set; }
public int returned { get; set; }
}
public class StoriesResourceItem
{
public string resourceURI { get; set; }
public string name { get; set; }
public string type { get; set; }
}
public class Events
{
public int available { get; set; }
public string collectionURI { get; set; }
public EventsResourceUriItem[] items { get; set; }
public int returned { get; set; }
}
public class EventsResourceUriItem
{
public string resourceURI { get; set; }
public string name { get; set; }
}
public class Url
{
public string type { get; set; }
public string url { get; set; }
}
}
This was a huge help! Hope someone else finds it useful.

I have the result of an API call which looks like:
{"Operations":[{"OperationId":"2","OperationObjectId":"Application","OperationName":"UnlockSession","OperationParameters":[{"Name":"viewModel","Value":"model"},{"Name":"returnUrl","Value":"https://"}],"OperationCaller":{"UserPrincipalName":"bob","ClientIPAddress":""},"OperationResult":"Succeeded","OperationStatus":200,"OperationRequest":{"Method":"POST","Url":""},"OperationStartedTime":"2013-08-20T12:04:17.5462357Z","OperationCompletedTime":"2013-08-20T12:04:17.9979469Z"}],"ContinuationToken":null}
Ideally I want to convert it to an object so I can do stuff like:
object.OperationObjectID; // gives Application
object.Method; // gives POST
object.OperationResult; // gives Succeeded
Does any one know how that is done? Does the JSON parse need to be aware of the format?
Thanks,
Andrew

you can use Json.Net as below
dynamic object = JObject.Parse(yorjsonstring);
object.Operations[0].OperationObjectID;
object.Operations[0].Method;
object.Operations[0].OperationResult;
rather than using dynamic object you can generate classes for your json and serialize to those classes like below.
you can get help of http://json2csharp.com/ site for generate classes
public class OperationParameter
{
public string Name { get; set; }
public string Value { get; set; }
}
public class OperationCaller
{
public string UserPrincipalName { get; set; }
public string ClientIPAddress { get; set; }
}
public class OperationRequest
{
public string Method { get; set; }
public string Url { get; set; }
}
public class Operation
{
public string OperationId { get; set; }
public string OperationObjectId { get; set; }
public string OperationName { get; set; }
public List<OperationParameter> OperationParameters { get; set; }
public OperationCaller OperationCaller { get; set; }
public string OperationResult { get; set; }
public int OperationStatus { get; set; }
public OperationRequest OperationRequest { get; set; }
public string OperationStartedTime { get; set; }
public string OperationCompletedTime { get; set; }
}
public class RootObject
{
public List<Operation> Operations { get; set; }
public object ContinuationToken { get; set; }
}
then
RootObject obj = JsonConvert.DeserializeObject<RootObject>(jsonstring);
obj.Operations[0].OperationObjectID;

Try to use JavaScriptSerializer class: http://msdn.microsoft.com/ru-ru/library/system.web.script.serialization.javascriptserializer.aspx.