I have a JSON string that I am trying to parse, using C#. I have used JsonConvert to serialize my data into a JSON string.
Here is my sample JSON string:
{"names": ["John", "Joe", "Jack"], "nationality": "American"}
I am able to deserialize this string into an object using JsonConvert.DeserializeObject(x);
The problem is, I dont know how to read from the object, using C#. Can someone help me out?
public class People
{
[JsonProperty("names")]
public List<string> Names;
[JsonProperty("nationality")]
public string Nationality;
}
Other answers are technically correct, but using JsonPropertyAttribute is a universally accepted convention. Then use JsonConvert:
var people = JsonConvert.DeserializeObject<People>(x);
A better approach would be to define a class with the expected structure, then using JavaScriptSerializer to deserialize it:
class NameSet
{
public IList<string> names { get; set; }
public string nationality { get; set; }
}
var serializer = new JavaScriptSerializer();
var nameset = serializer.Deserialize<NameSet>(jsonString);
Create a custom class like this:
public class CustomData
{
public string[] Names { get; set; }
public string Nationality { get; set; }
public CustomData() { }
}
And use JsonConvert to deserialize yo an object of this type:
CustomData data = JsonConvert.DeserializeObject<CustomData>(x);
The following should suffice:
public class PeopleGroup {
public string[] names { get; set; }
public string nationality { get; set }
}
var myObject = JsonConvert.DeserializeObject<PeopleGroup>(x);
Basically, you create a strongly typed object, and deserialise directly into it.
If you don't want to actually define a class, you can use an anonymous type:
string json = "{\"names\": [\"John\", \"Joe\", \"Jack\"], \"nationality\": \"American\"}";
// Just defining the structure of the anonymous type
var x = new { names = new string[0], nationality = string.Empty };
x = JsonConvert.DeserializeAnonymousType(json, x);
You should use dataContractJsonSerializer class, it is faster and most important is it is inbuilt class of .Net Framework. I will post solution in my next commment, in that How can we use DataContractJsonSerializer class.Now I cant post solution because in my end net is too slow :(, but I will post today.
Related
I don't want to use Newtonsoft's Json.Net library. I'm avoiding any third-party dependencies if I can help it in this project.
If I have JSON that looks like this:
{
"has_more_items": false,
"items_html": "...",
"min_position": "1029839231781429248"
}
and I have a class that looks like this:
public class TwitterJson
{
bool hasMore { get; set; } // has_more_items
string rawText { get; set; } // items_html
string nextKey { get; set; } // min_position
}
and I have a JsonObject containing the above JSON:
JsonObject theJson = JsonObject.Parse(result);
How do I deserialize the JsonObject into my class? I've been trying to find a clear example of this, and everything I've found uses Json.Net.
I've been trying to find a clear example of this, and everything I've found uses Json.Net.
Because reinventing existing functionality is a waste of time especially when all the hard work has already been done for you.
If you insist on not using it then you will have to manually construct the object model based on the expected JSON.
For example, assuming publicly available properties
public class TwitterJson {
public bool hasMore { get; set; } // has_more_items
public string rawText { get; set; } // items_html
public string nextKey { get; set; } // min_position
}
Then parsing the above to the desired object model
JsonObject theJson = JsonObject.Parse(result);
var model = new TwitterJson {
hasMore = theJson.GetNamedBoolean("has_more_items"),
rawText = theJson.GetNamedString("items_html"),
nextKey = theJson.GetNamedString("min_position")
};
As mentioned by #Dimith, you need to decorate your class with [DataContract] and [DateMember], Please refer to below code which will convert your JSON into a given object.
// Deserialize a JSON string to a given object.
public static T ReadToObject<T>(string json) where T: class, new()
{
DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
using (MemoryStream stream = new MemoryStream(Encoding.UTF8.GetBytes(json)))
{
return ser.ReadObject(stream) as T;
}
}
Class:
[DataContract]
public class TwitterJson
{
[DataMember(Name = "has_more_items")]
bool hasMore { get; set; } // has_more_items
[DataMember(Name = "items_html")]
string rawText { get; set; } // items_html
[DataMember(Name = "min_position")]
string nextKey { get; set; } // min_position
}
Sample on how to use:
var result = "{\"has_more_items\": false, \"items_html\": \"...\",\"min_position\": \"1029839231781429248\"}";
var obj = ReadToObject<TwitterJson>(result);
You have to decorate your class with [DataContract] and [DataMember] attributes. Write the json into a memory stream and deserialize using DataContractJsonSerializer
Here is a more elaborated sample.
In addition to #Nkosi's answer below are some Comparisons between JSON.net and other alternatives:
JSON.Net vs DataContractJsonSerializer
JSON.Net vs Windows.Data.Json
I have a web service that is outputting JSON in the form
{"AppointmentList":[{"AppointmentList":{"id":"1","MeetingId":"1","MeetingName":"Test Meeting 1","Length":"90","Room":"B2C","DateTimeFrom":"1st Sept 2016","Venue":"The old pub","DateCreated":"2016-08-30 00:00:00","DateDue":"2016-09-01 00:00:00","UserId":"JohnsonPa"}},{"AppointmentList":{"id":"2","MeetingId":"2","MeetingName":"Test Meeting 2","Length":"60","Room":"B2C","DateTimeFrom":"11th Sept 2016","Venue":"The old pub","DateCreated":"2016-09-01 00:00:00","DateDue":"2016-09-12 00:00:00","UserId":"JohnsonPa"}...}]}
I am trying to deserialise this in to List. Normally, I would have a Base Class that would contain a property List AppointmentList {get; set;}, however, that would mean that I can't use type T and need a pile of duplicate code for each class.
I can certainly create BaseClass with a property public List Data {get; set;} however, as the JSON won't deserialise to Data (incorrect name) and the JSON PropertyName can't be set to the class name derived from typeof(T).ToString().
Is there a way to achieve what I'm trying to do without resorting to lots of code duplication?
I've tried casting the deserialiser to JArray and creating a reader from that, but this throws an exception.
Im not sure if this is exactly what you need, but maybe something like this would work? It allows you to successfully deserialize to a JArray like you state you tried at the end of your question.
JArray result = JsonConvert.DeserializeObject<dynamic>(json).AppointmentList;
Here how to convert it to List<object>
dynamic data = JsonConvert.DeserializeObject(json);
JArray array = data.AppointmentList;
List<object> objectList = array.ToObject<List<object>>();
What is wrong with generics? If you want a schemaless data structure use JObject or dynamic if not you can try this.
class Program
{
public const string json = #"{""AppointmentList"":[{""AppointmentList"":{""id"":""1"",""MeetingId"":""1"",""MeetingName"":""Test Meeting 1"",""Length"":""90"",""Room"":""B2C"",""DateTimeFrom"":""1st Sept 2016"",""Venue"":""The old pub"",""DateCreated"":""2016-08-30 00:00:00"",""DateDue"":""2016-09-01 00:00:00"",""UserId"":""JohnsonPa""}},{""AppointmentList"":{""id"":""2"",""MeetingId"":""2"",""MeetingName"":""Test Meeting 2"",""Length"":""60"",""Room"":""B2C"",""DateTimeFrom"":""11th Sept 2016"",""Venue"":""The old pub"",""DateCreated"":""2016-09-01 00:00:00"",""DateDue"":""2016-09-12 00:00:00"",""UserId"":""JohnsonPa""}}]}";
static void Main(string[] args)
{
var items = Newtonsoft.Json.JsonConvert.DeserializeObject<AppointmentItemList<Meeting1>>(json).GetList();
var items2 = Newtonsoft.Json.JsonConvert.DeserializeObject<AppointmentItemList<Meeting2>>(json).GetList();
Console.ReadLine();
}
public class AppointmentItemList<T>
{
public List<AppointmentItem> AppointmentList { get; set; }
public class AppointmentItem
{
public T AppointmentList { get; set; }
}
public IList<T> GetList()
{
return AppointmentList.Select(al => al.AppointmentList).ToList();
}
}
public class Meeting1
{
[Newtonsoft.Json.JsonProperty("id")]
public string Id { get; set; }
public string MeetingName { get; set; }
}
public class Meeting2
{
[Newtonsoft.Json.JsonProperty("id")]
public string Id { get; set; }
public string Room { get; set; }
}
}
I have a string in JSON format as follows
string jsonStr = "{"Type":1, "Id":1000,"Date":null,"Group": "Admin","Country":"India","Type":1}";
I want to modify this string so that Id attribute should always be the first. The order of attributes matters.
Is there any way I can modify this string.
I tried searching google but did not find appropriate solution.
Any help would be appreciated.
EDIT:
I also tried to deserialize object using
object yourOjbect = new JavaScriptSerializer().DeserializeObject(jsonStr);
But here also the "type" attribute comes first. I dont find any way to move the attributes within this deserialized object
It's possible. Use the JsonProperty attribute, property Order.
http://www.newtonsoft.com/json/help/html/JsonPropertyOrder.htm.
Let me know if it works.
Instead of attempting to manipulate the order of the outputted JSON and comparing strings, I would transform both JSON strings that you want to compare, into objects and then perform your comparison. You could then compare individual properties or entire objects with something like the following:
void CompareJSON()
{
string json = #"{""Type"":1, ""Id"":1000,""Date"":null,""Group"": ""Admin"",""Country"":""India"",""Type"":1}";
string jsonToCompare = "JSON TO COMPARE";
MyObject myJsonObject = JsonConvert.DeserializeObject<MyObject>(json);
MyObject myJsonObjectToCompare = JsonConvert.DeserializeObject<MyObject>(jsonToCompare);
if (myJsonObject.Id == myJsonObjectToCompare.Id)
{
// Do something
}
}
class MyObject
{
public int Id { get; set; }
public int Type { get; set; }
public DateTime? Date { get; set; }
public string Group { get; set; }
public string Country { get; set; }
}
Please note that this example is carried out using the Newtonsoft.JSON library. More information on the library can be found here.
Just make your JSON into a c# class with Id first and then serialize it again if that is what you need. You do know that you have "Type" twice in the JSON string? In this solution it will get "fixed" so you only have it once as it should be. But if your string really is with two Type this wont work since the strings will be incorrect. If they really are like that you need to do some ugly string manipulation to fix the order but i hope the first string is incorrect only here and not in your code.
private void Test() {
string json = #"{""Type"":1, ""Id"":1000,""Date"":null,""Group"": ""Admin"",""Country"":""India"",""Type"":1}";
JavaScriptSerializer jsonSerializer = new JavaScriptSerializer();
MyJsonObject myJsonObject = jsonSerializer.Deserialize<MyJsonObject>(json);
string s = jsonSerializer.Serialize(myJsonObject);
//Returns: {"Id":1000,"Type":1,"Date":null,"Group":"Admin","Country":"India"}
}
class MyJsonObject {
public int Id { get; set; }
public int Type { get; set; }
public DateTime? Date { get; set; }
public string Group { get; set; }
public string Country { get; set; }
}
I'm trying to get the data from a website RSS converting it to JSON. I got this JSON string:
http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&q=http%3A%2F%2Frss.tecmundo.com.br%2Ffeed
I'm using lists to get the values but I got this error "Cannot create an instance of the abstract class or interface" and I don't know how to solve it. It happens in this line.
IList<News> content = new IList<News>();
Here is my code.
public class News
{
public string author { get; set; }
public string title { get; set; }
public string content { get; set; }
public string contentSnippet { get; set; }
public string link { get; set; }
public string publishedDate { get; set; }
public string[] getFeed(string Website)
{
string path = #"http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&q=" + Website;
var json = new WebClient().DownloadString(path);
JObject jsonObject = JObject.Parse((string)json);
IList<JToken> jsonData = jsonObject["responseData"]["feed"]["entries"]["0"].Children().ToList();
IList<News> content = new IList<News>();
foreach(JToken data in jsonData)
{
News finalData1 = JsonConvert.DeserializeObject<News>(jsonData.ToString());
content.Add(finalData1);
}
return new string[] { "I must return something here." };
}
}
Here is the tool I'm using to visualize better the JSON string: http://jsonschema.net/#/
The error you're getting has nothing to do with JSON. It is because you're trying to create an instance of an interface. You could just fix that by giving it the concrete List<T> class:
IList<News> content = new List<News>();
However, the simpler way of converting the IList<JToken> to an IList<News> is probably to use LINQ again - you can do all of this in one step pretty easily:
IList<News> content = jsonObject["responseData"]["feed"]["entries"]["0"]
.Children()
.Select(token => JsonConvert.DeserializeObject<News>(token.ToString())
.ToList();
That compiles, but isn't actually want due to the data you've got. entries is an array, so you probably want:
JArray array = (JArray) jsonObject["responseData"]["feed"]["entries"];
var content = array
.Select(token => JsonConvert.DeserializeObject<News>(token.ToString())
.ToList();
Your problem has nothing to do with the json, but with trying to create an instance of an interface which is not possible in c#. You need to create an instance of a concrete class that implements the IList interface. List would be one example. There are others, including arrays.
I need to deserialize the following Json, which according to Jsonlint.com is valid, but ive not come across this before or cannot find examples of similar Json and how to deal with it?
[1,"Bellegrove / Sherwood ","76705","486","Bexleyheath Ctr",1354565507000]
My current system with like this:
Data class:
[DataContract]
public class TFLCollection
{ [DataMember(Name = "arrivals")]
public IEnumerable<TFLB> TFLB { get; set; }
}
[DataContract]
public class TFLB
{
[DataMember]
public string routeName { get; set; }
[DataMember]
public string destination { get; set; }
[DataMember]
public string estimatedWait { get; set; }
}
Deserializer:
DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(TFLCollection));
using (var stream = new MemoryStream(Encoding.Unicode.GetBytes(result)))
{ var buses = (TFLCollection)serializer.ReadObject(stream);
foreach (var bus in buses.TFLBuses)
{
StopFeed _item = new StopFeed();
_item.Route = bus.routeName;
_item.Direction = bus.destination;
_item.Time = bus.estimatedWait;
listBox1.Items.Add(_item);
My exsiting deserializer works with a full Json stream and iterates through it, but in my new Json I need to deserialize, it only have 1 item, so I wont need to iterate through it.
So is it possible to deserialize my Json example using a similar method than I currently do?
I would say that you are attempting to overcomplicate things. What you have is a perfectly formed json array of strings. If I were you I would deserialize that to an .net array first, and then write a 'mapper' function to copy the values across:
public TFLB BusRouteMapper(string[] input)
{
return new TFLB {
Route = input[x],
Direction = input[y],
};
}
And so on. Of course this assumes that you know what order your json is going to be in, but if you are attempting this in the first place then you must do!