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UWP Json to C# conversion

I want to serialize some json data I get from the web to classes and use the data, so I went to http://json2csharp.com/ and turned the json as below
json: [{"line_descr":"\u03a0\u0395\u0399\u03a1\u0391\u0399\u0391\u03a3 -
\u0392\u039f\u03a5\u039b\u0391","line_descr_eng":"PEIRAIAS - VOYLA"}]
To this class:
public class RootObject
{
public string line_descr { get; set; }
public string line_descr_eng { get; set; }
}
This is my code:
class LineName
{
public async static Task<RootObject> GetLineName(int linecode)
{
var http = new HttpClient();
var response = await http.GetAsync("http://telematics.oasa.gr/api/?act=getLineName&p1=962");
var result = await response.Content.ReadAsStringAsync();
var serializer = new DataContractJsonSerializer(typeof(RootObject));
var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));
var data = (RootObject)serializer.ReadObject(ms);
return data;
}
}
[DataContract]
public class RootObject
{
[DataMember]
public string line_descr { get; set; }
[DataMember]
public string line_descr_eng { get; set; }
}
private async void Button_Click(object sender, RoutedEventArgs e)
{
RootObject myLine = await LineName.GetLineName(92);
ResultTextBlock.Text = myLine.line_descr_eng;
}
So when I try to get the data and display it in my textblock I get the error: line_descr_eng is null.
Can someone point where the fault is ? since the line_descr_eng should be
PEIRAIAS - VOYLA but mine is null and after a lot of searching I cant find where the fault is.

Your json is an array, not an object, and you should deserialize it into an array.
public async static Task<RootObject[]> GetLineName(int linecode)
{
var http = new HttpClient();
var response = await http.GetAsync("http://telematics.oasa.gr/api/?act=getLineName&p1=962");
var result = await response.Content.ReadAsStringAsync();
var serializer = new DataContractJsonSerializer(typeof(RootObject[]));
var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));
var data = (RootObject[])serializer.ReadObject(ms);
return data;
}
//...
var myLines = await LineName.GetLineName(92);
var myLine = myLines.FirstOrDefault();
Also you don't need a memory stream, you can read stream from the http response
var result = await response.Content.ReadAsStreamAsync();

You simple can use the JavaScriptSerializer class instead of DataContractJsonSerializer like this:
Replace:
var serializer = new DataContractJsonSerializer(typeof(RootObject));
var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));
var data = (RootObject)serializer.ReadObject(ms);
with this:
var ser = new JavaScriptSerializer();
var test = ser.Deserialize<List<RootObject>>(json);
If you cannot find JavaScriptSerializer, then you have to do the simple following steps:
Right click References and do Add Reference, then from Assemblies->Framework select System.Web.Extensions.
Now you should be able to add the following to your class file:
using System.Web.Script.Serialization;
Cited from: https://stackoverflow.com/a/15391388/5056173

Parsing multiple objects using Jobject in Newtonsoft.Json.Linq

I am trying to parse the result from the google speech to text API. The json response is :
{"result":[]}
{"result":[
{"alternative":[
{"transcript":"hello Google how are you feeling","confidence":0.96274596},
{"transcript":"hello Google how are you today","confidence":0.97388196},
{"transcript":"hello Google how are you picking","confidence":0.97388196},
{"transcript":"hello Google how are you kidding","confidence":0.97388196}
]
,"final":true}]
,"result_index":0
}
Now i am trying to parse it through JObject. The problem is occurring in parsing the Result object which is appearing twice so, how do i parse the second Result object. Here is my code which i am trying is :
StreamReader SR_Response = new StreamReader(HWR_Response.GetResponseStream());
Console.WriteLine(SR_Response.ReadToEnd()+SR_Response.ToString());
String json_response = SR_Response.ReadToEnd() + SR_Response.ToString();
JObject joo = JObject.Parse(json_response);
JArray ja = (JArray)joo["result"];
foreach (JObject o in ja)
{
JArray ja2 = (JArray)o["alternative"];
foreach (JObject h in ja2)
{
Console.WriteLine(h["transcript"]);
}
}
Next solution i tried using deserialize object code is:
string responseFromServer = (SR_Response.ReadToEnd());
String[] jsons = responseFromServer.Split('\n');
String text = "";
foreach (String j in jsons)
{
dynamic jsonObject = JsonConvert.DeserializeObject(j);
if (jsonObject == null || jsonObject.result.Count <= 0)
{
continue;
}
Console.WriteLine((string)jsonObject["result"]["alternative"][0]["transcript"]);
text = jsonObject.result[0].alternative[0].transcript;
}
Console.WriteLine("MESSAGE : "+text);

What you have is a series of JSON root objects concatenated together into a single stream. As explained in Read Multiple Fragments With JsonReader such a stream can be deserialized by setting JsonReader.SupportMultipleContent = true. Thus, to deserialize your stream, you should first introduce the following extension methods:
public static class JsonExtensions
{
public static IEnumerable<T> DeserializeObjects<T>(Stream stream, JsonSerializerSettings settings = null)
{
var reader = new StreamReader(stream); // Caller should dispose
return DeserializeObjects<T>(reader, settings);
}
public static IEnumerable<T> DeserializeObjects<T>(TextReader textReader, JsonSerializerSettings settings = null)
{
var ser = JsonSerializer.CreateDefault(settings);
var reader = new JsonTextReader(textReader); // Caller should dispose
reader.SupportMultipleContent = true;
while (reader.Read())
{
if (reader.TokenType == JsonToken.None || reader.TokenType == JsonToken.Undefined || reader.TokenType == JsonToken.Comment)
continue;
yield return ser.Deserialize<T>(reader);
}
}
}
Next, using a code-generation utility such as http://json2csharp.com/, generate c# classes for a single JSON root object, like so:
public class Alternative
{
public string transcript { get; set; }
public double confidence { get; set; }
}
public class Result
{
public List<Alternative> alternative { get; set; }
public bool final { get; set; }
}
public class RootObject
{
public List<Result> result { get; set; }
public int result_index { get; set; }
}
And deserialize as follows:
List<RootObject> results;
using (var stream = HWR_Response.GetResonseStream())
{
results = JsonExtensions.DeserializeObjects<RootObject>(stream).ToList();
}
Having done this you can use standard c# programming techniques such as Linq to enumerate the transcript values, such as:
var transcripts = results
.SelectMany(r => r.result)
.SelectMany(r => r.alternative)
.Select(a => a.transcript)
.ToList();
If you don't want define a fixed data model for your JSON collection, you can deserialize directly to a list of JObject like so:
List<JObject> objs;
using (var stream = HWR_Response.GetResonseStream())
{
objs = JsonExtensions.DeserializeObjects<JObject>(stream).ToList();
}
Then you can use SelectTokens() to select the values of all the "transcript" properties nested inside each object:
var transcripts = objs
// The following uses the JSONPath recursive descent operator ".." to pick out all properties named "transcript".
.SelectMany(o => o.SelectTokens("..transcript"))
.Select(t => t.ToString())
.ToList();
Updated sample fiddle showing both options.

Convert Json Singleton into List Phone 81 UAP

I am using http client to return a json response from a webservice. The example I am following here is from code project tutorial. However its example only returns into a var, it was created for the method to be called on screen I am changing it to be called from within a class. I have removed the webservice for security.
My Main question is how would I change this function to return a List of cinemas instead of the var variable I have a class created as such. I tried changing var into List but i noticed json.net handles this list so I need return the var as a known object instead I think?.
public class City
{
public string id { get; set; }
public string timing_title { get; set; }
}
public class Citys
{
public List<City> city { get; set; }
}
I just don't know what to do to convert this so it returns a list of citys for me to use in function.
This is a list of example json data returned.
{"city":[{"id":"5521","timing_title":"Lahore"},{"id":"5517","timing_title":"Karachi"},{"id":"5538","timing_title":"Islamabad"},{"id":"5535","timing_title":"Rawalpindi"},{"id":"5518","timing_title":"Hyderabad"},{"id":"5512","timing_title":"Faisalabad"},{"id":"8028","timing_title":"Gujranwala"},{"id":"8027","timing_title":"Gujrat"}]}
public async void GetCinemasList()
{
try
{
using (HttpClient client = new HttpClient())
{
client.BaseAddress = new Uri("webserviceurl");
var url = "index.php/webservice/upcoming_movie";
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.GetAsync(url);
if (response.IsSuccessStatusCode)
{
var data = response.Content.ReadAsStringAsync();
var cityData = JsonConvert.DeserializeObject<City>(data.Result.ToString());
}
}
}
catch (Exception ex)
{
// MessageBox.Show("Some Error Occured");
}
}

You have a string holding a JSON value.
You can parse and iterate through JSON values like this:
var data = "{\"city\":[{\"id\":\"5521\",\"timing_title\":\"Lahore\"},{\"id\":\"5517\",\"timing_title\":\"Karachi\"},{\"id\":\"5538\",\"timing_title\":\"Islamabad\"},{\"id\":\"5535\",\"timing_title\":\"Rawalpindi\"},{\"id\":\"5518\",\"timing_title\":\"Hyderabad\"},{\"id\":\"5512\",\"timing_title\":\"Faisalabad\"},{\"id\":\"8028\",\"timing_title\":\"Gujranwala\"},{\"id\":\"8027\",\"timing_title\":\"Gujrat\"}]}";
JsonObject rootObject;
if (JsonObject.TryParse(data, out rootObject))
{
JsonArray cityArray = rootObject.GetNamedArray("city");
foreach (var jsonValue in cityArray)
{
JsonObject cityObject = jsonValue.GetObject();
Debug.WriteLine(cityObject.GetNamedString("timing_title"));
}
}
else
{
// Invalid JSON data.
}
Output:
Lahore
Karachi
Islamabad
Rawalpindi
Hyderabad
Faisalabad
Gujranwala
Gujrat

RavenDB Concurrent Update Using .NET Client

I'd like to know what happens given the following scenario using the .net client.
using (IDocumentSession session = documentStore.OpenSession())
{
thingToUpdate = session.Load<TUpdateThing>(id);
// Modify thingToUpdate here
// ** Someplace else the object is updated and saved. **
session.SaveChanges(); // What happens here?
}
Will this automatically throw an error based on the etag having changed, or will this go off and overwrite the changes made by somebody else?
I've seen some stuff on this in relation to the http api:
http://ravendb.net/docs/http-api/http-api-comcurrency

What you're talking about is optimistic concurrency. If you want to use that, you set
session.Advanced.UseOptimisticConcurrency = true;
By default, it's not set.
Here's a passing test that demonstrates this:
public class ConcurrentUpdates : LocalClientTest
{
[Fact]
public void ConcurrentUpdatesWillThrowAConcurrencyException()
{
using (var store = NewDocumentStore())
{
var originalPost = new Post { Text = "Nothing yet" };
using (var s = store.OpenSession())
{
s.Store(originalPost);
s.SaveChanges();
}
using (var session1 = store.OpenSession())
using (var session2 = store.OpenSession())
{
session1.Advanced.UseOptimisticConcurrency = true;
session2.Advanced.UseOptimisticConcurrency = true;
var post1 = session1.Load<Post>(originalPost.Id);
var post2 = session2.Load<Post>(originalPost.Id);
post1.Text = "First change";
post2.Text = "Second change";
session1.SaveChanges();
// Saving the second text will throw a concurrency exception
Assert.Throws<ConcurrencyException>(() => session2.SaveChanges());
}
using (var s = store.OpenSession())
{
Assert.Equal("First change", s.Load<Post>(originalPost.Id).Text);
}
}
}
public class Post
{
public string Id { get; set; }
public string Text { get; set; }
}
}

How to convert a List<T> to specific Json format

I want to be able to convert a List<T> into a specific JSON table-like format. In my case, the T will always be a simple object (no nested properties). Here are two examples to illustrate what I want.
Example #1: List<Person> to JSON
// C# list of Persons
var list = new List<Person>() {
new Person() { First = "Jesse", Last = "Gavin", Twitter = "jessegavin" },
new Person() { First = "John", Last = "Sheehan", Twitter = "johnsheehan" }
};
// I want to transform the list above into a JSON object like so
{
columns : ["First", "Last", "Twitter"],
rows: [
["Jesse", "Gavin", "jessegavin"],
["John", "Sheehan", "johnsheehan"]
]
}
Example #2: List<Address> to JSON
// C# list of Locations
var list = new List<Location>() {
new Location() { City = "Los Angeles", State = "CA", Zip = "90210" },
new Location() { City = "Saint Paul", State = "MN", Zip = "55101" },
};
// I want to transform the list above into a JSON object like so
{
columns : ["City", "State", "Zip"],
rows: [
["Los Angeles", "CA", "90210"],
["Saint Paul", "MN", "55101"]
]
}
Is there a way to tell JSON.net to serialize an object in this manner? If not, how could I accomplish this? Thanks.
UPDATE:
Thanks to #Hightechrider's answer, I was able to write some code that solves the problem.
You can view a working example here https://gist.github.com/1153155

Using reflection you can get a list of properties for the type:
var props = typeof(Person).GetProperties();
Given an instance of a Person p you can get an enumeration of the property values thus:
props.Select(prop => prop.GetValue(p, null))
Wrap those up in a generic method, add your favorite Json serialization and you have the format you want.

Assuming your using .Net 4 this should do everything you want. The class actually lets you convert to either XML or JSON. The Enum for CommunicationType is at the bottom. The serializer works best if the class your passing it has been decorated with DataContract & DataMember attributes. I've included a sample at the bottom. It will also take an anonymous type so long as it's all simple types.
Reflection would work as well but then you have to understand all the JSON nuances to output complex data types, etc. This used the built-in JSON serializer in .Net 4. One more note, because JSON does not define a date type .Net puts dates in a funky ASP.Net custom format. So long as your deserializing using the built-in deserializer it works just fine. I can dig up the documentation on that if you need.
using System;
using System.Xml.Serialization;
using System.Text;
using System.Runtime.Serialization.Json;
using System.IO;
using System.Xml.Linq;
internal class Converter
{
public static string Convert<T>(T obj, CommunicationType format, bool indent = false, bool includetype = false)
{
if (format == CommunicationType.XML)
{
return ToXML<T>(obj, includetype, indent);
}
else if (format == CommunicationType.JSON)
{
return ToJSON<T>(obj);
}
else
{
return string.Empty;
}
}
private static string ToXML<T>(T obj, bool includetype, bool indent = false)
{
if (includetype)
{
XElement xml = XMLConverter.ToXml(obj, null, includetype);
if(indent) {
return xml.ToString();
}
else
{
return xml.ToString(SaveOptions.DisableFormatting);
}
}
else
{
System.Xml.Serialization.XmlSerializerNamespaces ns = new System.Xml.Serialization.XmlSerializerNamespaces();
XmlSerializer xs = new XmlSerializer(typeof(T));
StringBuilder sbuilder = new StringBuilder();
var xmlws = new System.Xml.XmlWriterSettings() { OmitXmlDeclaration = true, Indent = indent };
ns.Add(string.Empty, string.Empty);
using (var writer = System.Xml.XmlWriter.Create(sbuilder, xmlws))
{
xs.Serialize(writer, obj, ns);
}
string result = sbuilder.ToString();
ns = null;
xs = null;
sbuilder = null;
xmlws = null;
return result;
}
}
private static string ToJSON<T>(T obj)
{
DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
using (MemoryStream ms = new MemoryStream())
{
string result = string.Empty;
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
ser.WriteObject(ms, obj);
result = encoding.GetString(ms.ToArray());
ms.Close();
encoding = null;
ser = null;
return result;
}
}
}
[DataContract()]
public enum CommunicationType : int
{
[XmlEnum("0"), EnumMember(Value = "0")]
XML = 0,
[XmlEnum("1"), EnumMember(Value = "1")]
JSON = 1
}
[DataContract(Namespace = "")]
public partial class AppData
{
[DataMember(Name = "ID")]
public string ID { get; set; }
[DataMember(Name = "Key")]
public string Key { get; set; }
[DataMember(Name = "Value")]
public string Value { get; set; }
[DataMember(Name = "ObjectType")]
public string ObjectType { get; set; }
}

Any specific reason why you don't need the standard format?
To actually answer the question:
Since this is something that is outside of JSON syntax I can't think of a way to implement this within the default framework.
One solution would be to leverage attributes decorate the properties you want transported over the wired with a custom attribute and using Reflection cycle through the properties and output their property names as the column headers and then cycle throw the objects and write the values. Generic enough so it could be applied across other objects as well.
public class Location
{
[JsonFooAttribute("City")]
public string city {get;set;}
[JsonFooAttribute("State")]
public string state {get;set;}
}