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DataContractSerializer returns null for all the variables when I try to deserialize

I have a problem where DataContractSerializer returns null for all my variable. It's like it doesn't see them or something. I'm using it to deserialize a json file into an object. I had it working for another json file that was using another class with 3 string attributes. This one is composed of 40 attributes mostly string and a few bool. I have been working on it for hours and I just can't seem to find what I'm doing wrong. I even tried it with only 1 string attribute and it still returned null. Here is a simplified version with only 1 string attribute and 1 bool attribute. Any advice is more than appreciated.
Thank you
Json :
[{"Proposal_x0020_Type":"Lite Proposal","BI_x0020_Criteria_x0020_1":true}]
Function that tries to deserialize the string:
public Proposal[] Deserializer(string jsonFile)
{
MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(jsonFile));
DataContractJsonSerializer deserializer = new DataContractJsonSerializer(typeof(Proposal[]));
Proposal[] projectArr = (Proposal[])deserializer.ReadObject(ms);
Console.WriteLine(jsonFile);
Console.ReadLine();
return projectArr;
}
Class of the object that the deserializer should create:
namespace PMIS
{
[DataContract]
public class Proposal
{
[DataMember(Order = 0)]
public string Proposal_x0020_Type { get; set; }
[DataMember(Order = 1)]
public bool BI_x0020_Criteria_x0020_1 { get; set; }
}
}

I managed to find the problem by comparing the code of this Deserialization to a previous one that I had. The only difference was the name of the variables inside the Json file. The fact that they contain the Unicode for space (x00200) causes some problem inside the DataContractDeserializer. I believe that it is seeing it as space, so instead of seeing "Proposal_x0020_Type", it is seeing "Proposal_ _Type", but I'm not sure about it. Anyway, the solution was to remove x0020 from all the variables inside the Json file. After that it worked perfectly fine.

Converting JSON data into an object

I am very new to this.Pardon me if I make any mistakes.
I have data in JSON form.Can I read this data directly and use it in C# code ?
From what I understood from reading up on the internet,I think I have to convert it into an object form to use the data.Am I right ?
If yes,Then I saw this method to convert as below :
string data = JsonConvert.DeserializeObject<string>(getmyissue());
getmyissue is the function which returns a string which has data in json format.
This gives me an exception saying
"Error reading string.Unexpected Token."
Can someone guide me where am I going wrong ?
EDIT
MyIssue.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Example
{
public class MyIssue
{
public string name{get;set;}
public string description { get; set; }
public string created { get;set; }
public string updated{get;set;}
public string displayName { get; set; }
}
}
Program.cs
MyIssue obj=null;
try
{
obj = JsonConvert.DeserializeObject<MyIssue>(manager.getmyissue());
}
catch(Exception e)
{
Console.WriteLine(e.Message);
}
Console.WriteLine("Name: "+obj.name);

The easiest way to de-serialize Json in a C#/.NET program is to use the brilliant NewtonSoft JSON library.
There are numerous ways to do it, but I have to admit that the NS libs just get on with the task (and no I'm not a member of the team etc, just an Avid User :-) ).
To do what you want for example, if you had:
{'Name': 'A person', 'AllowAccess': true,'Areas': ['Sales','Admin']}
You would first build an object to represent it as follows:
public MyObject
{
public string Name { get; set; }
public bool AllowAccess { get; set; }
public List<string> Areas { get; set; }
}
Once you've done this, it's a simple case of just doing the following:
string jsonString = "// Your json formated string data goes here";
MyObject myObject = JsonConvert.DeserializeObject<MyObject>(jsonString);
The properties in your object should at that point, reflect the properties in the JSON data you sent to it.
You will of course need to add the NS JSON Libs to your project, either via NuGet or Manually, which ever is easier for you, everything you need to know about that is here:
How to install JSON.NET using NuGet?
The really good thing about NS JSON however is not the ease of use, but the fact that it can also do dynamic de-serialization.
This comes in handy if you've no idea what to expect in the JSON you receive, and so don't know ahead of time how to construct an object to hold the results.
Rather than repeat what others have said however, you can find more information of doing things dynamically in this stack overflow post:
Deserializing JSON using JSon.NET with dynamic data
Update
Looking at your JSON data you have way more fields/properties in there than your trying to parse, and none of the libraries in common use (To the best of my knowledge) will pick and choose the fields to copy, you either have an object that represents them all, or not at all, the later of which I believe is the problem your facing.
I have a rather neat "JSON" plug in for chrome, than when given a chunk of JSON data formats the output for me nicely and makes it easy to read, it also helps massively when defining objects, allowing you to see the full nested structure of your data, here are a series of images showing your JSON data formatted using this plugin:
I'm not going to paste anymore images in, but that goes on for another 4 pages!!
Now, some extra information that may help you.
I know from experience (I had to write a parser in PHP for these Jira webhooks) that within the Jira control panel, you can configure your webhooks to ONLY return the information your interested in.
Right now, it looks like you've just told the system to dump everything, for every event that you've hooked too (Which looks like - all of them), it's been a while since I did any work with these, but as well as a global webhook, you also have individual webhooks, which only fire on specific events and produce JSON data that's very much smaller than what your dealing with here.
I'd therefore advise you, to take a look in your Jira control panel (Or ask your Admin/Lead Dev/etc to take a look) and seriously trim down as much of that data as you can.
Further more, if memory serves me right, you can also make various web API calls to the Jira service to get this info too, and in that case you can tell the API exactly what your interested in, meaning it will only return the fields you need.
Right now, your main problem is the sheer volume of data your trying to deal with, if you tackle that problem, you'll find the issues surrounding the code your trying to get working will be very much easier to deal with.
Update 2
Just to make it clearer what I mean by using a "dynamic" type to get at your data, you would use something like the following code:
string jsonString = "// Your json formated string data goes here";
var result = JsonConvert.DeserializeObject<dynamic>(jsonString);
The difference here is that your using the C# dynamic type rather than a strongly typed object of your own design.
"dynamic" is useful, because it's kind of like having an empty object, and then having the properties added for you, without you having to define it.
What this essentially means is that, if you pass in the following JSON:
{'Name': 'A person', 'AllowAccess': true,'Areas': ['Sales','Admin']}
You'll end up with a dynamic object that looks like:
result = dynamic
{
public string Name { get; set; }
public bool AllowAccess { get; set; }
public List<string> Areas { get; set; }
}
thus:
result.Name
will get you access to the contents of the Name field and so on.
If your JSON was then changed to become:
{'Name': 'A person', 'AllowAccess': true,'Areas': ['Sales','Admin'], 'Location': 'The World' }
Your object would magically have a property called 'Location' containing the value 'The World' which you could access using:
result.Location
In your case, this would allow you to define your concrete object EG:
public MyObject
{
public string Name { get; set; }
public string Email { get; set; }
}
and then do something like the following (Assuming that your inbound JSON had properties in called Name & Email):
string jsonString = "// Your json formated string data goes here";
var result = JsonConvert.DeserializeObject<dynamic>(jsonString);
MyObject myObject = new MyObject
{
Name = result.Name,
Email = result.Email
}
You'd then discard the dynamic object as you'd not need it anymore.
The BIG problem your going to have with this approach is maintaining your models. Manual property assignment is all fine and dandy for a small handful of properties and objects, but it soon becomes a huge maintenance nightmare as your software grows.
I'm sure it doesn't take much to imagine what kind of task you'd be facing if you had to do this for 100 different JSON requests and 50 different types of objects.
For this reason, using this approach you should really consider using some kind of mapping technology such as "AutoMapper", however for now I'm going to advise you leave that until later before you start researching it, as it'll not help you to be clear about dealing with this dynamic approach.

The JSON you get is already a string, so converting it to string doesn't make much sense. You need to create classes that reflect the structure represented by the JSON string.
For example to convert the following JSON into objects, you'd have to create a class for the users:
{"user":{"name":"asdf","teamname":"b","email":"c","players":["1","2"]}}
public class User
{
public string name { get; set; }
public string teamname { get; set; }
public string email { get; set; }
public Array players { get; set; }
}
Then you should be able to use this:
JavaScriptSerializer jss= new JavaScriptSerializer();
List<User> users = jss.Deserialize<List<User>>(jsonResponse);

Parsing JSON with undefined value

How I can deserialize json in this case :
(json string I receive from server(in reality the string more and more complex) and can only change it(it's not well as I think) or customize parsing(deserializing) this string, but how do it I don't understand.....)
string json = "[{\"a\":384,\"type\":undefined,\"name\":\"A\"}, {\"a\":385,\"type\":2,\"name\":\"B\"}]";
var t = ser.Deserialize<List<CustClass>>(json);
"type":undefined - raise Exception " Invalid JSON primitive: undefined"
public class CustClass
{
public int a{ get; set; }
public string Name { get; set; }
}
I've try using JavaScriptConverter and JavaScriptTypeResolver but not solve the issue
may be json.net can help me? ....

You should be trying to avoid having things undefined if they are going to be serialized and deserialized. Set default values. Make sure that instead of undefined it passes in an empty string or default value.
If necessary, then I'd suggest checking first, you can do simple for loops through objects, but the easier, more efficient answer, is to not add excess.

How is your JSON being generated? It's complaining because undefined is not allowed as a JSON value. The value null is allowed in JSON, but you need to ensure it won't cause problems when deserialized into a CustClass object.

JSON Deserialization Type is not supported for deserialization of an array

I've read two other posts regarding the deserialization error, but I've not gotten anywhere so I'm posting my own question.
I have a WCF service that's returning JSON. Upon deserialization of a specific type, it fails.
In an effort to allow you to easily replicate the error, I've hardcoded the JSON below along with the call.
Essentially you should be able to copy/paste the code below and see it fail.
The consumer needs to deserialize this into a working object. s.Deserialize fails with the error message noted in the Title.
NOTE: I realize there are slashes in my JSON. Those are there for convenience to escape the quotes. Thanks.
Example code:
var s = new JavaScriptSerializer();
var jstr =
"[{\"UserId\":1,\"WorkoutId\":1,\"WorkoutInfo\":[\"Step 1\",\"Step 2\"]},{\"UserId\":2,\"WorkoutId\":2,\"WorkoutInfo\":[\"Step 1a\",\"Step 2a\"]},{\"UserId\":5,\"WorkoutId\":0,\"WorkoutInfo\":[\"new work1\",\"new work 1\",\"new work 1\"]}]";
Workout blah = s.Deserialize<Workout>(jstr);
var response = ServicePOST<Workout>("AddUserWorkout", workout);
and Workout class:
public class Workout
{
public int UserId { get; set; }
public List<string> WorkoutInfo { get; set; }
}

The problem is that you're telling the serializer that it's just a single Workout, not a list/array of them. This works:
var blah = s.Deserialize<List<Workout>>(jstr);
This isn't directly related to your question, but if at all possible, I'd recommend that you use Json.NET instead of JavaScriptSerializer.

MVC 4 ApiController not serializing System.Json.JsonObject properly

So I am new to working with MVC4 and the serialization of objects on the back end seems pretty "magical" to me so if I am doing this the wrong way please let me know.
My goal however is to build a simple rest API and return JSON out. I figured that I would use System.Json and just return JsonObject. I have simplified this down for the sake of this question but the objects are much more complicated in my real issue.
Here is my controller....
....
public class ActionsController : ApiController
{
// GET api/actions
public JsonObject Get()
{
JsonObject testObjet = new JsonObject();
testObjet.Add("Name", "Test name");
testObjet.Add("Description", "Test Description");
return testObjet;
}
....
I would expect to see:
{"Name":"Test name","Description":"Test Description"}
Instead I see:
{"Name":[],"Description":[]}
I actually seem to get better results when I return a string of the JsonObject or heck even just return the object itself with the exception it has enums and I want to return the names not the number values, which is what led me to JsonObject for customization.
Does anyone know why it is dropping off the values?
EDIT:
So because of Dan's comments below I tried just for giggles to see what the XML serializer spit out with the JSON object and I get the below exception...
"Type 'System.Json.JsonPrimitive' with data contract name 'JsonPrimitive:http://schemas.datacontract.org/2004/07/System.Json' is not expected."
So it appears that you can not serialize the System.Json.JsonObject object, because it uses a type that it does not expect.
That is shocking. Does anyone have a workaround? If not I am off to find out how to show enum names when serializing instead of values.

So the answer is apparently... You Can't!
It appears that the type JsonPrimitive is not supported to serialize objects. The answers provided below by Obi and Dan helped me to poke around a bit more and find out that the XML serializer actually throws an exception while the JSON serializer simply eats it and puts out an empty array which is what you see above.
There are any number of correct answers here.
Make your own custom serializer
Output JSON as a string
Return custom objects and then work around things like the Enum
values
I am sure there are others.
But whatever you do don't try to use System.Json as a return in the ApiController because you will get the results above.

You should not force your WebApi call to use a particular format like JSON. One of the features of WebApi is that you can specify the format as part of the request. Return an object from your Get call, and let the WebApi engine do the serialization and deserialization:
public class DataObject
{
public string Name { get; set; }
public string Description { get; set; }
}
public class ActionsController : ApiController
{
// GET api/actions
public DataObject Get()
{
var testObject = new DataObject
{
Name = "Test name",
Description = "Test Description"
};
return testObject;
}
}
You can specify the format by setting the Accept header to application/xml, application/json, etc.
The default JSON serializer has no problem serializing simple string properties like Name and Description.

I would suggest you did this instead
// GET api/actions
public object Get()
{
//New up a strongly typed object if you want to return a specific type
//and change Action return type accordingly
var testObjet = new (){
Name= "Test name",
Description= "Test Description"
};
return testObjet;
}
Dan has posted a similar answer below so let me try to address your other problem. To serialize the enum, I would suggest you hide it in a public string property which would return the string value of the enum,
public class DataObject{
public MyEnum SomeEnumValue;
public string EnumValue{
get {
//..return SomeEnumValue string value
}
}
}
You can then read the value from EnumValue which should be properly serialized as you want.