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C# Newtonsoft deserialize JSON array

I'm trying to deserialize an array using Newtonsoft so i can display files from a cloud based server in a listbox but i always end up getting this error no matter what i try:
Newtonsoft.Json.JsonReaderException: 'Unexpected character encountered while parsing value: [. Path '[0].priv', line 4, position 15.'
Thisis an example try to deserialize:
[
{
"code": 200,
"priv": [
{
"file": "file.txt",
"ext": "txt",
"size": "104.86"
},
{
"file": "file2.exe",
"ext": "exe",
"size": "173.74"
},
],
"pub": [
{
"file": "file.txt",
"ext": "txt",
"size": "104.86"
},
{
"file": "file2.exe",
"ext": "exe",
"size": "173.74"
}
]
}
]
I tried using a C# Class like this:
public class ListJson
{
[JsonProperty("pub")]
public List List { get; set; }
}
public class List
{
[JsonProperty("file")]
public string File { get; set; }
[JsonProperty("ext")]
public string Ext { get; set; }
[JsonProperty("size")]
public string Size { get; set; }
}
[JsonProperty("priv")]
public List List { get; set; }
}
public class List
{
[JsonProperty("file")]
public string File { get; set; }
[JsonProperty("ext")]
public string Ext { get; set; }
[JsonProperty("size")]
public string Size { get; set; }
}
And deserialize with:
List<list> fetch = Newtonsoft.Json.JsonConvert.DeserializeObject<List<list>>(json);

The correct C# class structure for your JSON is the following:
public class FileEntry
{
public string file { get; set; }
public string ext { get; set; }
public string size { get; set; }
}
public class FileList
{
public int code { get; set; }
public List<FileEntry> priv { get; set; }
public List<FileEntry> pub { get; set; }
}
Deserializing it in this way:
var fetch = JsonConvert.DeserializeObject<FileList[]>(json);
var fileList = fetch.First(); // here we have a single FileList object
As said in the other answer, creating a class called List doesn't automagically turn it into a collection of objects. You need to declare the types to be deserialized from an array a collection type (e.g. List<T>, T[], etc.).
Small tip: when in doubt, use json2csharp.com to generate strongly typed classes from a json string.

At the moment List has a single List instance called priv, which despite the name: doesn't make it a list. To deserialize a JSON array ("priv": [...]), it needs to an array or list-like type, for example List<T> for some T. Presumably a List<FileThing>, if we assume that FileThing is actually the second type called List (you have 2).

Parse complex JSON: multiple loops vs. classes

I have a Json of type :
{
"JobProcessors": [
{
"JobName": "ArchivalJob",
"IsEnabled": true,
"Batching": {
"BatchSize": 0,
"DegreeOfParallelism": -1
},
"Settings": {
"ArchivalJobCollectionPageSize": 50
}
},
{
"JobName": "AuditLogJob",
"IsEnabled": false,
"Batching": {
"BatchSize": 10,
"DegreeOfParallelism": -1
},
"Settings": {}
}
],
"ScheduledJobs": [
{
"JobName": "RemoteStartClientCommandJob",
"PrimaryAction": {
"ConnectionString": "#JobProcessorsIntegrationSBConnectionStringValue#",
"Settings": {
"LeadTimeInSeconds": "600",
"MaxSrsJobCount": 25
}
},
"ErrorAction": {
"ConnectionString": "#PairedJobProcessorIntegrationSBConnectionStringValue#",
"EntityPath": "remotestartqueue",
"Settings": {
"LeadTimeInSeconds": "600",
"MaxSrsJobCount": 25
}
}
}
]
}
I want to check the "IsEnabled" property for all "JobName" for which come under "JobProcessors" category.
In C# what i Have used till now is :
dynamic parsedJson = JsonConvert.DeserializeObject(reader.GetString(1));
foreach (var item in parsedJson)
{
foreach (var smallitem in item)
{
foreach (var tag in smallitem)
{
if(tag.IsEnabled.toString()=="true"){
Console.WriteLine("true");
}
}
}
}
This is giving me correct result except the fact that it also iterates for "ScheduledJobs" . But the main issue is :
Is this the right or most efficient way to do this ? If possible suggest some better method .
One that i know of is using classes , but i may not know the json structure beforehand. Also the json is very huge so making classes can be cumbersome !!

Given that you are already doing JObject.Parse(jsonstring); to parse your JSON string, you can use SelectTokens() with a JSONPath query to find all "JobName" objects under "JobProcessors":
// I want to check the "IsEnabled" property for all "JobName" for which come under "JobProcessors"
foreach (var job in root.SelectTokens("..JobProcessors[?(#.JobName)]"))
{
var isEnabled = (bool?)job["IsEnabled"];
Debug.WriteLine(string.Format("Job {0}: IsEnabled={1}", job["JobName"], isEnabled));
}
Notes:
.. is the recursive descent operator: it recursively descends the JToken hierarchy returning each item, subsequently to be matched against the remaining parts of the query string.
JobProcessors returns values of properties of that name.
[?(#.JobName)] returns array items (of JobProcessors in this case) that are objects with a JobName property.
(bool?) casts the value of "IsEnabled" to a boolean or null if missing.
And the output of this is:
Job ArchivalJob: IsEnabled=True
Job AuditLogJob: IsEnabled=False

As in your code snippet we are using two foreach it may take time for large object. So we can do the same thing in a single foreach or if you have some specific node to fetch or search we can use linq, and for this first we need to convert our json object into c# object. For converting Json object to C# you can use this site "http://json2csharp.com/" then we can Deserialize Json object into c#.
It will be something like this
string jsonString = "your Json Object as string";
var jsonObject = JsonConvert.DeserializeObject<RootObject>(jsonString);
foreach (JobProcessor obj in jsonObject.JobProcessors)
{
string JobName = obj.JobName;
bool value=obj.IsEnabled;
}
And I also converted given Json in c# object if the Json object is same you can directly use these classes.
public class Batching
{
public int BatchSize { get; set; }
public int DegreeOfParallelism { get; set; }
}
public class Settings
{
public int ArchivalJobCollectionPageSize { get; set; }
}
public class JobProcessor
{
public string JobName { get; set; }
public bool IsEnabled { get; set; }
public Batching Batching { get; set; }
public Settings Settings { get; set; }
}
public class Settings2
{
public string LeadTimeInSeconds { get; set; }
public int MaxSrsJobCount { get; set; }
}
public class PrimaryAction
{
public string ConnectionString { get; set; }
public Settings2 Settings { get; set; }
}
public class Settings3
{
public string LeadTimeInSeconds { get; set; }
public int MaxSrsJobCount { get; set; }
}
public class ErrorAction
{
public string ConnectionString { get; set; }
public string EntityPath { get; set; }
public Settings3 Settings { get; set; }
}
public class ScheduledJob
{
public string JobName { get; set; }
public PrimaryAction PrimaryAction { get; set; }
public ErrorAction ErrorAction { get; set; }
}
public class RootObject
{
public List<JobProcessor> JobProcessors { get; set; }
public List<ScheduledJob> ScheduledJobs { get; set; }
}
Hope this will help.
Thank you

Runtime Binder Exception

After a deserialization I save the content in an object:
var obj = JsonConvert.DeserializeObject<dynamic>(responseText);
so I execute a loop for populate a DataGrid
foreach(var item in obj)
{
MainWindow.AppWindow.Squadre_DataGrid.Items.Add(new Teams.Club_Information
{
code = item.code,
name = item.name,
shortName = item.shortName,
squadMarketValue = item.squadMarketValue
});
}
The problem's that inside the foreach the compiler show Runtime Binder Exception.
Why happean this?
Some more details:
Class structure
public class Self
{
public string href { get; set; }
}
public class Fixtures
{
public string href { get; set; }
}
public class Players
{
public string href { get; set; }
}
public class Links
{
public Self self { get; set; }
public Fixtures fixtures { get; set; }
public Players players { get; set; }
}
public class RootObject
{
public Links _links { get; set; }
public string name { get; set; }
public string code { get; set; }
public string shortName { get; set; }
public string squadMarketValue { get; set; }
public string crestUrl { get; set; }
}
JSON structure:
{
"_links": {
"self": { "href": "http://api.football-data.org/alpha/teams/19" },
"fixtures": { "href": "http://api.football-data.org/alpha/teams/19/fixtures" },
"players": { "href": "http://api.football-data.org/alpha/teams/19/players" }
},
"name": "Eintracht Frankfurt",
"code": "SGE",
"shortName": "Eintr. Frankfurt",
"squadMarketValue": "75.475.000 ?",
"crestUrl": "http://upload.wikimedia.org/wikipedia/commons/0/04/Eintracht_Frankfurt_Logo.svg"
}

The object you are deserializing does not contain a property named code. So the line code = item.code causes an exception at runtime, because the Json.Net object behind the dynamic does not contain a value named code.
This means that the Json that you are parsing does not contain a property named code. Or else it only sometimes contains a property named code. In that case you'll have to either parse it is a JObject and check if the property exists or create an type do deserialize it into.'
Edit
Based on the Json that you posted along with the class structure it looks like you should just be deserializing directly into a RootObject class:
var obj = JsonConvert.DeserializeObject<RootObject>(responseText);
Or in any case you can still deserialize into a dynamic but you need to get rid of the foreach since you don't have a collection of RootObject
var obj = JsonConvert.DeserializeObject<dynamic>(responseText);
MainWindow.AppWindow.Squadre_DataGrid.Items.Add(new Teams.Club_Information
{
code = obj.code,
name = obj.name,
shortName = obj.shortName,
squadMarketValue = obj.squadMarketValue
});
Where you went wrong was the foreach. Since obj is dynamic there is no compiler error and the Json.Net JObject that is returned supports iteraction. But the that gives you back each of the property values, (e.g. _links, name, etc) on at a time, not the object that you are interested in.

Parsing nested JSON--child properties are null

So I am trying to parse some JSON that is returned to me by a third party api that looks something like:
{
"status":"ok",
"links":
[
{
"link":
{
"link_name":"Sample",
"link_id":"9999"
}
},
],//and so on with other nested properties
I have created classes to map the JSON to
[DataContract]
public class JsonTestResults
{
[DataMember]
public string status { get; set; }
[DataMember]
public IEnumerable<Link> links { get; set; }
}
[DataContract]
public class Link
{
[DataMember]
public string link_name { get; set; }
[DataMember]
public string link_id { get; set; }
}
And I'm pushing the response through this deserializer (taken from this post
public T Deserialise<T>( string json )
{
T obj = Activator.CreateInstance<T>( );
using (MemoryStream ms = new MemoryStream( Encoding.Unicode.GetBytes( json ) ))
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer( obj.GetType( ) );
obj = (T)serializer.ReadObject( ms );
return obj;
}
}
However, my deserialized results are showing the contents of Link[] as null. (there is a Link object for each one returned, but the link_name and link_id are null.)
I've checked out this, this, this, this and this, but haven't been able to solve this issue. I am looking for a solution that doesn't require a third party library. (per my lead dev).
I don't believe it's a problem with the classes matching the JSON, but I can post the full code if anyone would like to review it.

You need one more class to deserialize it correctly
public class JsonTestResults
{
public string status { get; set; }
public IEnumerable<TempLink> links { get; set; }
}
public class TempLink
{
public Link link;
}
public class Link
{
public string link_name { get; set; }
public string link_id { get; set; }
}
I tested it with Json.Net and worked.
var obj = JsonConvert.DeserializeObject <JsonTestResults>(json);
JavaScriptSerializer also works
var obj2 = new JavaScriptSerializer().Deserialize<JsonTestResults>(json);

Its a syntax error in the JSON,
In a JSON Array the last element does not have a ',' after it.
{
"status":"ok",
"links":
[
{
"link":
{
"link_name":"Sample",
"link_id":"9999"
}
}
],
This will work !!

nested json c# object deserialization

i have the following json string (jsonString)
[
{
"name":"Fruits",
"references":[
{"stream":{"type":"reference","size":"original",id":"1"}},
],
"arts":[
{"stream":{"type":"art","size":"original","id":"4"}},
{"stream":{"type":"art","size":"medium","id":"9"}},
]
}
]
and the following C# objects
class Item
{
public string Name { get; set; }
public List<Stream> References { get; set; }
public List<Stream> Arts { get; set; }
public Item()
{
}
}
class Stream
{
public string Type { get; set; }
public string Size { get; set; }
public string Id { get; set; }
public Stream()
{
}
}
and the following code
Item item = JsonConvert.DeserializeObject<Item>(jsonString);
when I run the code, it creteas the correct number of references and arts, but each stream has null value (type = null, size = null).
is it posible to do this json.net deserializeobject method or should I manually deserialize ?

EDIT: Okay, ignore the previous answer. The problem is that your arrays (references and arts) contain objects which in turn contain the relevant data. Basically you've got one layer of wrapping too many. For example, this JSON works fine:
[
{
"name":"Fruits",
"references":[
{"Type":"reference","Size":"original","Id":"1"},
],
"arts":[
{"Type":"art","Size":"original","id":"4"},
{"type":"art","size":"medium","id":"9"},
]
}
]
If you can't change the JSON, you may need to introduce a new wrapper type into your object model:
public class StreamWrapper
{
public Stream Stream { get; set; }
}
Then make your Item class have List<StreamWrapper> variables instead of List<Stream>. Does that help?