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Json.Net Deserialize dictionary without property name

I already looked at a lot of other questions with the same problem but never found a definitive solution that actually works for me. I tried using the JsonExtensionData Attribute, that doesn't work though since I can't convert my other data class to an object and it throws the Invalid extension data attribute on 'NAMESPACE'. Member 'Sols' type must implement IDictionary<string, JToken>. error.
My current data model class looks like this
public partial class Mars
{
public Dictionary<string, Sol> Sols { get; set; }
[JsonProperty("sol_keys")]
public List<long> SolKeys { get; set; }
}
public partial class Sol
{
[JsonProperty("AT")]
public At At { get; set; }
[JsonProperty("First_UTC")]
public DateTimeOffset FirstUtc { get; set; }
[JsonProperty("Last_UTC")]
public DateTimeOffset LastUtc { get; set; }
[JsonProperty("Season")]
public string Season { get; set; }
}
public partial class At
{
[JsonProperty("av")]
public double Av { get; set; }
[JsonProperty("ct")]
public long Ct { get; set; }
[JsonProperty("mn")]
public double Mn { get; set; }
[JsonProperty("mx")]
public double Mx { get; set; }
}
The json data looks like this
{
"651":
{
"AT":
{
"av": -61.957,
"ct": 302204,
"mn": -96.733,
"mx": -15.877
},
"First_UTC": "2020-09-25T02:42:14Z",
"Last_UTC": "2020-09-26T03:21:49Z",
"Season": "summer"
},
"652": {
"AT": {
"av": -65.002,
"ct": 278608,
"mn": -96.111,
"mx": -15.653
},
"First_UTC": "2020-09-26T03:21:50Z",
"Last_UTC": "2020-09-27T04:01:24Z",
"Season": "summer"
},
"sol_keys": [
"646",
"647",
"648",
"649",
"650",
"651",
"652"
]
}
I can't really modify the json data since I get it from an api.
I basically just want to select one of the numbers and then get the Sol data of that object.
Any help would be appreciated.

The JSON doesn't fit well with the C# type system. However, you can still use Json.Net to parse it. You just need to introduce some extra steps.
First step is to parse the JSON to a JObject:
var jObject = JsonConvert.DeserializeObject<JObject>(json);
Then you can extract the sol_keys:
var solKeys = jObject.GetValue("sol_keys").ToObject<long[]>();
Now it becomes a bit tricky. If you remove the sol_keys from the JSON (in this case the parsed JSON) it has the structure of a dictionary of Sol objects that you are able to parse:
jObject.Remove("sol_keys");
var mars = jObject.ToObject<Dictionary<long, Sol>>();
Now you have both solKeys and mars parsed from the JSON. Furthermore the solKeys and the keys in the dictionary share the same type (long).

C# - extracting values from JSON object with "System" in property names

At the beginning I want to say that 'm not a C# developer by any means, however at my work I've received a task where I have to write simple web service in .net.
The task is not very complicated however I've encountered the problem that JSON payload which is sent to our web service has "System" in property names:
"resource": {
"fields": {
"System.AreaPath": "someData",
"System.TeamProject": "someData",
"System.IterationPath": "someData"
}
}
I'm trying to get those values by using:
public class Resource
{
public Fields System.AreaPath { get; set; }
}
However I'm getting an error ("System" is a namespace but used like a type.)
Are there any best practices on how to perform such task ?
Thank you.

One easy option it to specify the JSON property in an attribute. If you're using Json.NET you can use [JsonProperty] for this. Complete example:
using System;
using System.IO;
using Newtonsoft.Json;
public class Fields
{
[JsonProperty("System.AreaPath")]
public string AreaPath { get; set; }
[JsonProperty("System.TeamProject")]
public string TeamProject { get; set; }
[JsonProperty("System.IterationPath")]
public string IterationPath { get; set; }
}
public class Resource
{
public Fields Fields { get; set; }
}
class Program
{
static void Main()
{
string json = File.ReadAllText("test.json");
var resource = JsonConvert.DeserializeObject<Resource>(json);
Console.WriteLine(resource.Fields.TeamProject);
}
}
JSON (removed the "resource" part to make it a complete JSON document; I assume you know how to handle this if necessary):
{
"fields": {
"System.AreaPath": "someData",
"System.TeamProject": "team project",
"System.IterationPath": "someData"
}
}
Output: team project

json newtonsoft : Deserialize Object containing a list of string

I have the following issue with this json :
{
"EVTS": {
"EVT": [
{ "ID": "123456",
"KEY1" : "somekey",
"CATEG": [
"cat1",
"cat2",
"cat3"
]
}
]}
}
and this c# class:
public class myClass{
public string ID { get; set; }
public string KEY1 { get; set; }
public list<string> CATEG { get; set; }
}
public class ESObject1
{
[JsonProperty("EVT")]
public List<myClass> EVT { get; set; }
}
public class ESObject0
{
[JsonProperty("EVTS")]
public ESObject1 EVTS { get; set; }
}
}
here i call the deserializer :
ESObject0 globalobject = JsonConvert.DeserializeObject<ESObject0>(json);
But this last code doesnt work, i throws this exception : System.ArgumentException: Could not cast or convert from System.String to System.Collections.Generic.List1[System.String].`
Instead of list<string> i used string [] and only string nothing seems to work.
how can i deserialize this object correctly please.
Thank you.

There doesn't seem to be any apparent problem wit hyour code as this working example illustrates:
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
public class myClass
{
public string ID { get; set; }
public string KEY1 { get; set; }
public List<string> CATEG { get; set; }
}
public class ESObject1
{
[JsonProperty("EVT")]
public List<myClass> EVT { get; set; }
}
public class ESObject0
{
[JsonProperty("EVTS")]
public ESObject1 EVTS { get; set; }
}
class Program
{
static void Main()
{
string json =
#"{
""EVTS"": {
""EVT"": [
{
""ID"": ""123456"",
""KEY1"": ""somekey"",
""CATEG"": [
""cat1"",
""cat2"",
""cat3""
]
}
]
}
}";
ESObject0 globalobject = JsonConvert.DeserializeObject<ESObject0>(json);
foreach (string item in globalobject.EVTS.EVT[0].CATEG)
{
Console.WriteLine(item);
}
}
}
Maybe you just fed a wrong json value to the deserializer which doesn't look like as the one shown in your question. By the way, the one shown i nyour question is invalid JSON as you are missing a , after KEY1 property declaration.
UPDATE:
Now that you have shown your real JSON (coming from http://donnees.ville.quebec.qc.ca/Handler.ashx?id=69&f=JSON) it appears that there's a row where CATEG is not an array of strings but a simple string:
""CATEG"": ""Conférence""
Now that's a pretty bad design because they are mixing arrays and simple properties. I am afraid that in order to deal with this situation you will need to use JObjects and extract the information you need by testing the actual underlying type.
For example:
var obj = JObject.Parse(json);
var events = (JArray)obj["EVTS"]["EVT"];
foreach (JObject evt in events)
{
var categories = evt["CATEG"];
if (categories is JArray)
{
// you've got a list of strings so you can loop through them
string[] cats = ((JArray)categories)
.Select(x => x.Value<string>())
.ToArray();
}
else
{
// you've got a simple string
string cat = categories.Value<string>();
}
}

I have done this many times with many many headaches. My advice is take the json output and use a tool similar to this to write your class for you (http://json2csharp.com/).
Then go over any nullable variables and add nullable type (ex. using int? for int) where needed.

Questioning received JSON structure

I'm currently using a beta API (http://developer.riotgames.com/api/methods) which returns JSON for all the exposed methods.
I've been able to use JSON.NET to deserialize all of these return values so far. However, today I consumed one of their function which returns a JSON that is valid but is in my opinion not correct.
You're probably wondering, why don't you ask it on the beta forum? I have but I haven't received an answer so far and in general this intrigues me.
A snippet of the JSON return:
"1001": {
"name": "Boots of Speed",
"plaintext": "Slightly increases Movement Speed",
"group": "BootsNormal",
"description": "<...
}
The problem I have with this structure is that the ID is used as a "group" without an identifier. I would be able to use this decently if it had
"ItemID" : "1001"
But it doesn't have that. I don't mind manually parsing it but I'd first like to know whether or not this JSON is correct (not just valid).
Do you agree that this is not a clean way of creating a JSON block that contains a list of elements or am I missing something here? So far I haven't seen any comments on the beta forum of this API so I'm really wondering why.
Edit "valid" vs "correct/usable":
I know it's a valid JSON statement. I'm questioning the fact whether this is usable with JSON.NET.
I have the following class definition (with two subclasses):
public class JSONItem
{
[JsonProperty("tags")]
public string[] Tags { get; set; }
[JsonProperty("plaintext")]
public string Plaintext { get; set; }
[JsonProperty("description")]
public string Description { get; set; }
[JsonProperty("name")]
public string Name { get; set; }
[JsonProperty("into")]
public string[] Into { get; set; }
[JsonProperty("image")]
public JSONItemImage Image { get; set; }
[JsonProperty("colloq")]
public string Colloq { get; set; }
[JsonProperty("gold")]
public JSONItemGold Gold { get; set; }
}
When giving the above JSON block to to JSONConvert.DeserializeObject(json) it throws an error because "1001" is not mentioned in JSONItem.
How do you handle this so that you can use JSON.NET?
A class like this won't work because you have no names to give the properties:
public class JSONItemWrapper
{
[JsonProperty("")]
public string ID { get; set; }
[JsonProperty("")]
public JSONItem MyProperty { get; set; }
}
Edit: "consistent with other methods"
The other methods return blocks where every property is within {} and has an identifier. The most recently added function have this "primary key outside of {}" style.

It is a valid json and you can use a type like Dictionary<string, SomeObject> to deserialize your json.
string json = #"{
""1001"": {
""name"": ""Boots of Speed"",
""plaintext"": ""Slightly increases Movement Speed"",
""group"": ""BootsNormal"",
""description"": ""desc...""
}
}";
var dict = JsonConvert.DeserializeObject<Dictionary<string, MyObject>>(json);
and accesing an item later on by its key can be fast too.
public class MyObject
{
public string name { get; set; }
public string plaintext { get; set; }
public string group { get; set; }
public string description { get; set; }
}

It's annoying when APIs do things like this (using numbers as property names), but all is not lost. Simply deserialize the JSON using Json.NET and then access each of the items using the indexer operator on the parent object.
EDIT:
I almost never create DTOs when deserializing JSON. It's lots of unnecessary boilerplate in most cases. I prefer deserializing to a dynamic object, but that won't be as effective when dealing with property names that begin with digits.
Here is how I would deserialize your sample message:
using System;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
namespace JsonExample
{
internal class Program
{
private static void Main()
{
const string json = #"
{
'1001': {
'name': 'Boots of Speed',
'plaintext': 'Slightly increases Movement Speed',
'group': 'BootsNormal',
'description': '<...'
}
}";
var jObject = JsonConvert.DeserializeObject<JObject>(json);
var plaintext = jObject["1001"]["plaintext"].Value<string>();
Console.WriteLine(plaintext);
}
}
}

When put into http://JSONLint.com,
{
"1001": {
"name": "Boots of Speed",
"plaintext": "Slightly increases Movement Speed",
"group": "BootsNormal",
"description": "<..."
}
}
Validates as JSON.

Parsing JSON data in C#

I have a JSON data as follows
{"id": "367501354973","from": {
"name": "Bret Taylor",
"id": "220439" }
which is returned by an object(result) of IDictionary[String, Object]
In my C# code:
I have made a class for storing the JSON value which is as follows
public class SContent
{
public string id { get; set; }
public string from_name { get; set; }
public string from_id { get; set; }
}
My main C# function which stores the parses the JSON data and stores the value inside the class properties is as follows:
List<object> data = (List<object>)result["data"];
foreach (IDictionary<string, object> content in data)
{
SContent s = new SContent();
s.id = (string)content["id"];
s.from_name = (string)content["from.name"];
s.from_id = (string)content["from.id"];
}
When i execute this code, i get an exception saying System cannot find the Key "from.name" and "from.id"
When i comment the two lines (s.from_name = (string)content["from.name"];s.from_id = (string)content["from.id"];) my code runs fine.
I think i am not able to refer the nested JSON data properly.
Can anyone just validate it and please tell me how to refer nested data in JSON in C#?
Thanks

I'm not sure how you are parsing the JSON string. Are you using a class in the Framework to do the deserialization?
You could use the JavaScriptSerializer Class defined in the System.Web.Script.Serialization Namespace (you may need to add a reference to System.Web.dll)
Using that class, you would write your code like this:
public class SContent
{
public string id { get; set; }
public SFrom from { get; set; }
}
public class SFrom
{
public string name { get; set; }
public string id { get; set; }
}
Then deserialization looks like this:
var json = new JavaScriptSerializer();
var result = json.Deserialize<SContent>(/*...json text or stream...*/);
See JavaScriptSerializer on MSDN. You might also want to check out this similar question.