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How to deserialize json object with no parent class?

I'm trying and failing to write a program that will make an API call and then turn the returned items into objects that fit my model. Specifically I can't make it deserealize, and I suspect it has something to do with how the json is return compared to what my model looks like.
The data I'm trying to get looks like this;
https://api.nasa.gov/planetary/apod?start_date=2022-03-01&end_date=2022-03-08&api_key=DEMO_KEY
As you can see, it consists of an array of items, but there is no name for the array items. When I paste this into the Get-model with Paste JSON as Classes, I get this;
public class GetApodItemsResult
{
public Class1[] Property1 { get; set; }
}
public class Class1
{
public string copyright { get; set; }
public string date { get; set; }
public string explanation { get; set; }
public string hdurl { get; set; }
public string media_type { get; set; }
public string service_version { get; set; }
public string title { get; set; }
public string url { get; set; }
}
My entire code works just fine up until I need to serialize the JSON with this line:
var responseObject = await response.Content.ReadFromJsonAsync<GetApodItemsResult>();
, where I get this message;
System.Text.Json.JsonException: 'The JSON value could not be converted to UnnamedSpaceProject.Models.GetApodItemsResult.
Interestingly I know that the code works on a spotify api call, so the code really should work largely the same, which leads me to believe that the problem is with how the JSON is formatted.
How do I get around that? Because I don't see a way to have the root object contain an unnamed array.

Your GetApodItemsResult class is not a valid class to deserialize the content you get from server, the correct deserialization type will be List<Class1> or Class1[]
var responseObject = await response.Content.ReadFromJsonAsync<List<Class1>>();
I recommend you to use more meaningful name instead of Class1 you can name it Apod (acronym for Astronomy Picture of the Day)
Full working code:
using System.Text.Json;
using System.Text.Json.Serialization;
HttpClient client = new HttpClient();
const string BaseUrl = #"https://api.nasa.gov/";
var response = await client.GetAsync($"{BaseUrl}planetary/apod?start_date=2022-03-01&end_date=2022-03-08&api_key=DEMO_KEY");
if ((response.StatusCode != System.Net.HttpStatusCode.OK))
{
Console.Error.WriteLine("field to fetch data from server");
}
var responseBody = await response.Content.ReadAsStringAsync();
var pictuersList = JsonSerializer.Deserialize<List<Apod>>(responseBody);
Console.WriteLine($"there is {pictuersList?.Count} apod downloaded successflly");
Console.WriteLine("done");
public class Apod
{
[JsonPropertyName("copyright")]
public string Copyright { get; set; } = "";
[JsonPropertyName("date")]
public string Date { get; set; } = "";
[JsonPropertyName("explanation")]
public string Explanation { get; set; } = "";
[JsonPropertyName("hdurl")]
public string Hdurl { get; set; } = "";
[JsonPropertyName("media_type")]
public string MediaType { get; set; } = "";
[JsonPropertyName("service_version")]
public string ServiceVersion { get; set; } = "";
[JsonPropertyName("title")]
public string Title { get; set; } = "";
[JsonPropertyName("url")]
public string Url { get; set; } = "";
}

The object your JSON containing is not some container with the array in it, it IS the array. So, the correct code would be like this:
var responseObject = await response.Content.ReadFromJsonAsync<Class1[]>();
The correct JSON for your code would look like this:
{
"Property1": [{
"copyright": "Jeff DaiTWAN",
"date": "2022-03-01",
"url": "https://apod.nasa.gov/apod/image/2203/DuelingBands_Dai_960.jpg"
}]
}

How can I convert a json string to a json array using Newtonsoft?

I am using this code to read a json file firstSession.json and display it on a label.
var assembly = typeof(ScenarioPage).GetTypeInfo().Assembly;
string jsonFileName = "firstSession.json";
Stream stream = assembly.GetManifestResourceStream($"{assembly.GetName().Name}.{jsonFileName}");
using (var reader = new StreamReader(stream))
{
var json = reader.ReadToEnd(); //json string
var data = JsonConvert.DeserializeObject<SessionModel>(json);
foreach (SessionModel scenario in data)
{
scenarioName.Text = scenario.title;
break;
}
scenarioName.Text = data.title; // scenarioName is the name of the label
}
SessionModel.cs looks like:
public class SessionModel : IEnumerable
{
public int block { get; set; }
public string name { get; set; }
public string title { get; set; }
public int numberMissing { get; set; }
public string word1 { get; set; }
public string word2 { get; set; }
public string statement1 { get; set; }
public string statement2 { get; set; }
public string question { get; set; }
public string positive { get; set; } // positive answer (yes or no)
public string negative { get; set; } // negative answer (yes or no)
public string answer { get; set; } // positive or negative
public string type { get; set; }
public string format { get; set; }
public string immersion { get; set; }
public IEnumerator GetEnumerator()
{
throw new NotImplementedException();
}
}
The beginning of my json is:
{
"firstSession": [
{
"block": 1,
"name": "mark",
"title": "mark's house",
"numberMissing": 1,
"word1": "distracted",
"word2": "None",
"statement1": "string 1",
"statement2": "None",
"question": "question",
"positive": "No",
"negative": "Yes",
"answer": "Positive",
"type": "Social",
"format": "Visual",
"immersion": "picture"
},
I am getting a Newtonsoft.Json.JsonSerializationException: Cannot deserialize the current JSON object into type "MyProject.SessionModel" because the type requires a JSON array to deserialize correctly. To fix this error either change the JSON to a JSON array or change the deserialized type so that it is a normal .NET type that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. Path 'firstSession', line 2, position 17.
How can I convert the json string to a json array? Or make one of the other modifications the debugger suggests?

you need to create a wrapper class (json2csharp.com will help you do this)
public class Root {
public List<SessionModel> firstSession { get; set; }
}
then
var data = JsonConvert.DeserializeObject<Root>(json);
data.firstSession will be a List<SessionModel>

Create a new Class and have firstSession as List of SessionModel.
public class Sessions
{
public List<SessionModel> firstSession { get; set; }
}
Remove IEnumerable from the SessionModel
public class SessionModel
{
public int block { get; set; }
public string name { get; set; }
public string title { get; set; }
}
Change thedeserialization part as follows
var data = JsonConvert.DeserializeObject(line);
foreach (SessionModel scenario in data.firstSession)
{
//Here you can get each sessionModel object
Console.WriteLine(scenario.answer);
}

Getting NULL values while deserializing complex json

My project has a 3rd party web API that returns a json string in the following format (including the starting and ending curly braces):
{
"866968030210604":{
"dt_server":"2019-02-07 12:21:27",
"dt_tracker":"2019-02-07 12:21:27",
"lat":"28.844968",
"lng":"76.858502",
"altitude":"0",
"angle":"154",
"speed":"9",
"params":{
"pump":"0",
"track":"1",
"bats":"1",
"acc":"0",
"batl":"4"
},
"loc_valid":"1"
},
"866968030221205":{
"dt_server":"2019-02-07 12:20:24",
"dt_tracker":"2019-02-07 12:19:41",
"lat":"28.845904",
"lng":"77.096063",
"altitude":"0",
"angle":"0",
"speed":"0",
"params":{
"pump":"0",
"track":"1",
"bats":"1",
"acc":"0",
"batl":"4"
},
"loc_valid":"1"
},
"866968030212030":{
"dt_server":"0000-00-00 00:00:00",
"dt_tracker":"0000-00-00 00:00:00",
"lat":"0",
"lng":"0",
"altitude":"0",
"angle":"0",
"speed":"0",
"params":null,
"loc_valid":"0"
}
}
I want to deserialize it into a c# class object for further processing. I made the following class structure for the same:
class Params
{
public string pump { get; set; }
public string track { get; set; }
public string bats { get; set; }
public string acc { get; set; }
public string batl { get; set; }
}
class GPSData
{
public string dt_server { get; set; }
public string dt_tracker { get; set; }
public string lat { get; set; }
public string lng { get; set; }
public string altitude { get; set; }
public string angle { get; set; }
public string speed { get; set; }
public Params ObjParams { get; set; }
public string loc_valid { get; set; }
}
and I am trying the following code to deserialize:
JavaScriptSerializer jSerObj = new JavaScriptSerializer();
List<GPSData> lstGPSData = (List<GPSData>)jSerObj.Deserialize(json, typeof(List<GPSData>));
But every time it is showing NULL values assigned to each property of the class after the Deserialize() method is called. Please help me on this.

Your json is not in list format so deserializing to List<> isn't work
So you need to deserialize it into Dictionary<string, GPSData> like
JavaScriptSerializer jSerObj = new JavaScriptSerializer();
Dictionary<string, GPSData> lstGPSData = (Dictionary<string, GPSData>)jSerObj.Deserialize(json, typeof(Dictionary<string, GPSData>));
Usage:
foreach (var item in lstGPSData)
{
string key = item.Key;
GPSData gPSData = item.Value;
}
Also, you can list all your GPSData from above dictionary like,
List<GPSData> gPSDatas = lstGPSData.Values.ToList();
Output: (From Debugger)

JSON model binding with variable keys .net mvc4

What is a useful model which could bind a json object with arbitrary keys? Assume your json could look like:
{"##hello": "address","#world": "address1","name": "address"}
or
{"##hello": "address","#world": "address1","firstname": "foo", "lastname":"bar"}
or
{"##hello": "address","#world": "address1","children": [{"name":"foo"},{"name":"bar"}]}
So that means you only know at run time how the json model looks like. My current state is, that it seems the best practice is to send the json object as string to the controller and deserialize the json string it to an object.
public ActionResult mappingNodes(string model) {
dynamic json = Newtonsoft.Json.JsonConvert.DeserializeObject(model);
}

public class Children
{
[JsonProperty("name")]
public string Name { get; set; }
}
public class YourClass
{
[JsonProperty("##hello")]
public string Hello { get; set; }
[JsonProperty("#world")]
public string World { get; set; }
[JsonProperty("name")]
public string Name { get; set; }
[JsonProperty("firstname")]
public string FirstName { get; set; }
[JsonProperty("lastname")]
public string LastName { get; set; }
[JsonProperty("children")]
public Children[] Children { get; set; }
}
var json1 = "{ '##hello': 'address','#world': 'address1','name': 'address'}";
var json2 = "{ '##hello': 'address','#world': 'address1','name': 'address', 'firstname': 'foo', 'lastname':'bar'}";
var json3 = "{ '##hello': 'address','#world': 'address1','name': 'address','children': [{'name':'foo'},{'name':'bar'}]}";
var model1 = JsonConvert.DeserializeObject<YourClass>(json1);
var model2 = JsonConvert.DeserializeObject<YourClass>(json2);
var model3 = JsonConvert.DeserializeObject<YourClass>(json3);

Parsing JSON using Newtonsoft.JSON

I have a JSON string as follows:
[{
"ID":"1",
"title":"New Product Launch",
"fro":"Vitamin D",
"summary":"New Vitamin D prodcut",
"type":"image",
"link":"http:\/\/www.foo.in\/upload\/image\/1.png",
"detail":"13-11-2013",
"fileSize":23763
},
{
"ID":"2",
"title":"New Product Launch",
"fro":"Vitamin D",
"summary":"New Vitamin D prodcut",
"type":"image",
"link":"http:\/\/www.foo.in\/upload\/image\/1.png",
"detail":"13-11-2013",
"fileSize":23763
}]
My code for parsing is as follows:
AnnouncementListObject resultsJSON = JsonConvert.DeserializeObject<AnnouncementListObject>(json); //line1
using (AnnouncementDataContext context = new AnnouncementDataContext(Con_String))
{
AnnouncementData alData = new AnnouncementData();
alData.announcementID = int.Parse(resultsJSON.ID);
.
.
.
.
context.AnnouncementData.InsertOnSubmit(alData);
context.SubmitChanges();
}
EDIT:
public class AnnouncementListObject
{
public string ID { get; set; }
public string title { get; set; }
public string fro { get; set; }
public string summary { get; set; }
public string type { get; set; }
public string link { get; set; }
public string detail { get; set; }
public object fileSize { get; set; }
}
But it throws error on line 1 where I deserialize the JSON data. I want to store this multiple data rows in database. I cannot use foreach loop here as JSON data is not enclosed under root node. Any help on how should I go about?

Try deserializing to a list like so
var resultsJSON = JsonConvert.DeserializeObject<List<AnnouncementListObject>>(json); //line1
You're dealing with an array of JSON objects, but you're trying to cast it as a single object.