Develop Reference

How Can I Deserialize JSON Data Using C#?

I have seen some other questions like this, but those are quite complex JSON data's that have objects within objects. Although the JSON I'm working with is never static, I doubt it's as complex as those. Also, it's my first time using JSON with C# so I'm a little clueless.
What I'm trying to achieve is to separate the data that is received from an API that I prompt using WebRequest in C#.
{
"johhny.debt": {
"id":35187540,
"name":"johnny.debt",
"profileIconId":786,
"Level":30,
"revisionDate":1428019045000
}
}
The returned JSON data is in a fashion like thereof.
I want to be able to access all of the properties of the above string in the following manner:
ID :
Name:
~~
~~
~~
... and so forth.
I'm assuming some type of class has to be made for this?
All help is appreciated, thank you all in advance.

Install Json.Net from Nuget
Install-Package Newtonsoft.Json
https://www.nuget.org/packages/Newtonsoft.Json/
Declare class for inner object ({"id":..., "name": ... }):
public class InnerObject
{
[JsonProperty("id")]
public int Id { get; set; }
[JsonProperty("name")]
public string Username { get; set; }
[JsonProperty("profileIconId")]
public int ProfileIconId { get; set; }
[JsonProperty("level")]
public int Level { get; set; }
[JsonProperty("revisionDate")]
public string RevisionDate { get; set; }
}
As you can see you can specify rename mapping from json fields to .Net object properties using JsonPropertyAttribute.
Read your json to Dictionary<string,InnerObject> and get value of "johhny.debt" key:
var dict = JsonConvert.DeserializeObject<Dictionary<string, InnerObject>>(jsonText);
var johhny = dict["johhny.debt"];
Or if your need always to parse exact json property 'johhny.debt', you could create root object class:
public class RootObject
{
[JsonProperty("johhny.debt")]
public InnerObject JohhnyDept { get; set; }
}
And deserialize it:
var root = JsonConvert.DeserializeObject<RootObject>(jsonText);
var johhny = root.JohhnyDebt;

Just Create a class like this
public class RootObject
{
public int Id { get; set; }
public string name { get; set; }
public int profileIconId { get; set; }
public int Level { get; set; }
public string revisionDate { get; set; }
}
then install json.Net and this code to your main method
var jsonObject=JsonConvert.DeserializeObject<RootObject>(jsonText);
That's all
Update
var obj = JObject.Parse(json);
var RootObject = new RootObject()
{
Id = (int)obj["johhny.debt"]["id"],
Level = (int)obj["johhny.debt"]["Level"],
name = (string)obj["johhny.debt"]["name"],
profileIconId = (int)obj["johhny.debt"]["profileIconId"],
revisionDate = (string)obj["johhny.debt"]["revisionDate"]
};

JavaScriptSerializer.Deserialize Gives Null Fields

I sent the following JSON to a WCF service which accepts Stream as a parameter.
{"ReservationStream":
{"clientFirstName":"Abe",
"clientLastName":"Lincoln",
"clientPhone":"0544944860",
"clientEmail":"abe#mail.com",
"pickupLocationID":"3699",
"pickupAddressString":"JFK Airport Terminal 1",
"pickupFlightNumber":"LY001",
"pickupAirline":"El Al",
"pickupAirportName":"John F Kennedy Intl",
}
}
In the debugger, the stream variable shows all values as expected. I want to deserialize into a class defined as follows:
public class ReservationStream
{
public String clientFirstName { get; set; }
public String clientLastName { get; set; }
public String clientPhone { get; set; }
public String clientEmail { get; set; }
public String pickupLocationID { get; set; }
public String pickupAddressString { get; set; }
public String pickupFlightNumber { get; set; }
public String pickupAirline { get; set; }
public String pickupAirportName { get; set; }
}
When I call
JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
ReservationStream structuredReservations = javaScriptSerializer.Deserialize<ReservationStream>(strJSON);
no exception is thrown, but all of the fields have null values. Where is my mistake?

I think it's because your JSON object is nested inside a ReservationStream tag.
Try with just:
{
"clientFirstName":"Abe",
"clientLastName":"Lincoln",
"clientPhone":"0544944860",
"clientEmail":"abe#mail.com",
"pickupLocationID":"3699",
"pickupAddressString":"JFK Airport Terminal 1",
"pickupFlightNumber":"LY001",
"pickupAirline":"El Al",
"pickupAirportName":"John F Kennedy Intl"
}

You're trying to deserialize an object containing a ReservationStream object rather than the ReservationStream object itself.
One way to get around this is to make a wrapper class which contains a ReservationStream and deserialize using this:
public class WrapperClass
{
public ReservationStream ReservationStream { get; set; }
}
WrapperClass wrapperClass = serializer.Deserialize<WrapperClass>(strJSON);

I once have the same problem and I removed the javaScriptSerializer and directly used the method parameter like this
public static string UpdateTemplateProperties(TemplateProperties templateProperties)
{
var x = templateProperties.Something
}
and I have the javascript object structure as you
just be sure to have the same name for the parameter and the first object-name in your javascript object literal

Turn string into json C#

I have this sample code that i am working with. The json is a result of the http post.
var json = #"{'user': {
'country':'US',
'email':'testapi#example.com',
'first_name':'Test',
'last_name':'API',
'phone':null,
'zip':null,
'login_url':'https://new.site.com/xlogin/12325/abd9832cd92'
}
}";
var jsonSerializer = new JavaScriptSerializer();
var itemsList = (IDictionary<string, object>)jsonSerializer.DeserializeObject(json);
var url = itemsList["user.login_url"];
On itemsList["user.login_url"] i am getting the following error:
The given key was not present in the dictionary.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
Source Error:
Line 545: var jsonSerializer = new JavaScriptSerializer();
Line 546: var itemsList = (IDictionary<string, object>)jsonSerializer.DeserializeObject(json);
Line 547: var url = itemsList["user.login_url"];
Line 548: }
Line 549:
Am i doing something wrong here? How should i access the first name, last name and url etc from this object?
Alternately, how can i tie this result to a class that has following properties? I just need a pointer to a good resource.
public class User
{
public string Country { get; set; }
public string Email { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Phone { get; set; }
public string Zip { get; set; }
public string LoginUrl { get; set; }
}
Thanks.

Well I really don't understand why u are using IDictionary to parse json object.
Use Newtonsoft.Json instead of jsonSerializer much more essay to use.
Go on http://json2csharp.com/ and generate your class to define you json (copy json and result is C# class).
Now tie your json to new RootObject not user:
using System;
using Newtonsoft.Json;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
var json = #"{'user': {
'country':'US',
'email':'testapi#example.com',
'first_name':'Test',
'last_name':'API',
'phone':null,
'zip':null,
'login_url':'https://new.site.com/xlogin/12325/abd9832cd92'
}
}";
RootObject userObj = JsonConvert.DeserializeObject<RootObject>(json.ToString());
}
}
//generated with http://json2csharp.com/
public class User
{
public string country { get; set; }
public string email { get; set; }
public string first_name { get; set; }
public string last_name { get; set; }
public object phone { get; set; }
public object zip { get; set; }
public string login_url { get; set; }
}
public class RootObject
{
public User user { get; set; }
}
}

"user.login_url" is the property path you'd expect to use in JavaScript ... try accessing the dictionary keys instead
var user = itemsList["user"] as IDictionary<string,object>;
var url = user["login_url"] as string;

itemsList["user"] contains a second Dictionary. So you can navigate down to the login_url variable using
var user = (IDictionary<string, object>)itemsList["user"];
var login_url = user["login_url"];

Try using http://json.net/ it will give you a Dictionary with the types you want..

How do I deserialize a JSON array and ignore the root node?

I have next response from server -
{"response":[{"uid":174952xxxx,"first_name":"xxxx","last_name":"xxx"}]}
I am trying to deserialize this in next way -
JsonConvert.DeserializeObject<T>(json);
Where T = List of VkUser, but I got error.
[JsonObject]
public class VkUser
{
[JsonProperty("uid")]
public string UserId { get; set; }
[JsonProperty("first_name")]
public string FirstName { get; set; }
[JsonProperty("last_name")]
public string LastName { get; set; }
}
I always tryed
public class SomeDto // maybe Response as class name will fix it but I don't want such name
{
public List<VkUser> Users {get;set;}
}
What deserialization options can help me?

Use SelectToken:
string s = "{\"response\":[{\"uid\":174952,\"first_name\":\"xxxx\",\"last_name\":\"xxx\"}]}";
var users = JObject.Parse(s).SelectToken("response").ToString();
var vkUsers = JsonConvert.DeserializeObject<List<VkUser>>(users);
as pointed out by Brian Rogers, you can use ToObject directly:
var vkUsers = JObject.Parse(s).SelectToken("response").ToObject<List<VkUser>>();

reading JSON data remotely

UPDATE 1
i try to implement and but when i hover over my topic and i see the TopicId and TopicName are null and i see the data in myJSON string.
what else i have to do? what i am missing?
Topic topic = new Topic();
MemoryStream stream1 = new MemoryStream(Encoding.Unicode.GetBytes(myJSON));
//stream1.Position = 0;
DataContractJsonSerializer serialize = new DataContractJsonSerializer(typeof(Topic));
//topic = (Topic)serialize.ReadObject(stream1);
Topic p2 = (Topic)serialize.ReadObject(stream1);
stream1.Close(); //later i will use in `using statement`
stream1.Dispose();
PS: i just have only Topic class is that enough or do i have to create all the classes that jcolebrand showed below?
i have created a class called Topic and in it i have two prop
[DataContract]
public class Topic
{
[DataMember]
public string TopicId { get; set; }
[DataMember]
public string TopicName { get; set; }
}
UPDATE 1 END
I am working on a requirement that returns JSON data and I need a way to parse the data and load that data into a dropdownlist and I'm looking for the element in JSON called TopicName
after the TopicName is extracted I will load that data into a DropDownList asp.net control
(not using JQuery or JavaScript)
here is JSON data:
[{"NS":{"Count":1},
"Source":{"Acronym":"ABC","Name":"Name"},
"Item":[{"Id":"12312",
"Url":"http://sitename",
"ContentItem":[{"NS":{"Count":1},
"SourceUrl":"sitename",
"ContentType":"text/xml",
"PersistentUrl":"sitename",
"Title":"MY TITLE",
"SelectionSpec":{"ClassList":"","ElementList":"","XPath":null},
"Language":{"Value":"eng","Scheme":"ISO 639-2"},
"Source":{"Acronym":"ABC","Name":"Name","Id":null},
"Topics":[{"Scheme":"ABC",
"Topic":[{"TopicId":"6544","TopicName":"TOPIC NAME1"},
{"TopicId":"63453","TopicName":"TOPIC NAME2"},
{"TopicId":"2343","TopicName":"TOPIC NAME3"},
{"TopicId":"2342","TopicName":"TOPIC NAME4"}]
}],
"ContentBody":null
}]
}]
},
[{"NS":{"Count":1},"Source":{"Acronym":"ABC1","Name":"Name1"},"Item":[{"Id":"123121","Url":"http://sitename1","ContentItem":[{"NS":{"Count":1},"SourceUrl":"sitename","ContentType":"text/xml","PersistentUrl":"sitename1","Title":"MY TITLE1","SelectionSpec":{"ClassList":"","ElementList":"","XPath":null},"Language":{"Value":"eng","Scheme":"ISO 639-2"},
"Source":{"Acronym":"ABC1","Name":"Name1","Id":null},"Topics":[{"Scheme":"ABC1","Topic":[{"TopicId":"65441","TopicName":"TOPIC NAME11"},{"TopicId":"634531","TopicName":"TOPIC NAME21"},{"TopicId":"23431","TopicName":"TOPIC NAME31"},{"TopicId":"23421","TopicName":"TOPIC NAME41"}]}],"ContentBody":null}]}]},

Assuming the re-indent as applied above is correct, then you have the following classes (apparently)
public class OuterWrapper {
public NS NS { get; set; }
public Source Source { get; set; }
public ContentItemWrapper[] Item { get; set; }
}
public class ContentItemWrapper {
public int Id { get; set; }
public string Url { get; set; }
public ContentItem[] ContentItem { get; set; }
}
public class ContentItem {
public NS NS { get; set; }
public SourceUrl { get; set; }
// I'm gonna skip a bunch of fields, you get the idea
public Topics Topic { get; set; }
}
public class Topics {
public string Scheme { get; set; }
public Topic[] Topic { get; set; }
}
public class Topic {
public string TopicId { get; set; }
public string TopicName { get; set; }
}
And what you do is you use that set of type declarations (specifically the OuterWrapper) to DataContractJsonSerializer decode the JSON into a C# object that you can then query using strongly typed methods, etc. This is one of those times where C# doesn't have anywhere near the flexibility of Javascript, because everything has to be explicitly declared.

Try using built in serializer for JSON - http://msdn.microsoft.com/en-us/library/bb412179.aspx : new DataContractJsonSerializer(typeof(Person)).ReadObject(stream1);.
If it is not enough to read your objects consider using JSON.Net ( http://json.codeplex.com/) - JsonConvert.DeserializeObject<Labels>(json);