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How do I populate my model in C# MVC view model with data from C# API JSON? [duplicate]

This question already has answers here:
Read Json Serialized c#
(2 answers)
Closed 3 years ago.
I wanted to be able to access my data from anywhere so I made a c# data API that returns json for gets and accepts json for posts. All methods use HTTPResponseMessage as a return type so that I can send back the appropriate responses.
In jquery ajax its a simple thing to use and it works great but when I try to use c# mvc I am completely lost where and how to get the data returned from my API into the data model.
I tried using this in my viewModel. It got the data but then what
static public object GetProfile()
{
string url = "http://localhost:50121/api/Profile/1";
var client = new WebClient();
var content = client.DownloadString(url);
var serializer = new JavaScriptSerializer();
var jsonContent = serializer.Deserialize<object>(content);
return jsonContent;
}
public readonly object d = GetProfile();
Sorry if I am posting this wrong I have not asked questions here a lot.
I just want to populate my model with the json returned from the api call.

This line:
var jsonContent = serializer.Deserialize<object>(content);
Should be changed to:
var jsonContent = serializer.Deserialize<YourModelClass>(content);
Where YourModelClass is the model that you want to deserialise into.

Deserialize json straight to your model class (ModelClass in this example since you did not provide your model class definition).
using Newtonsoft.Json;
static public ModelClass GetProfile()
{
string url = "http://localhost:50121/api/Profile/1";
var client = new WebClient();
//object serialised as json string
var content = client.DownloadString(url);
//object deserialised as ModelClass
var model = JsonConvert.DeserializeObject<ModelClass>(json);
return model;
}

Unable to Parse JSON Response

I have a service that sends JSON response. The controller method looks as follows:
string varStr = "{proper JSON here}";
public string GetListofResourcesInSubscription(string subscriptionId)
{
// Uncomment any option below to test. The error persists either way.
//return varStr; --- Option 1
return JsonConvert.SerializeObject(JObject.Parse(varStr)); // Option 2
}
The method that gets the response is like the following:
response = outgoingRequest.GetResponse() as HttpWebResponse;
if (response.StatusCode == HttpStatusCode.OK)
{
responseStream = response.GetResponseStream();
using (var reader = new StreamReader(responseStream))
{
string strResp = reader.ReadToEnd();
JObject joResponse = JObject.Parse(strResp); // throws error
JArray objArray = (JArray)joResponse["value"];
// other processing
}
}
Irrespective of the return statement selected in the controller method above, the response parser is always throwing an error while it is trying to parse the response.
Changing the parsing line to the following resolves the issue but it is not clear to me why it is so.
JObject joResponse = JObject.Parse(JsonConvert.DeserializeObject<string>(strResp));
Also, I want to know what is the correct way of sending a JSON response from an ASP.NET web api2 controller. I don't want to use models for creating the response because I have JSON strings that I want to return directly instead of creating models out of them.
Update 1:
The error is the following:
"Error reading JObject from JsonReader. Current JsonReader item is not an object: String. Path '', line 1, position 6546."} System.Exception {Newtonsoft.Json.JsonReaderException}

You can't deserialize a complex JSON object back to a string. Your example won't work, because you are assuming the JSON evaluates to a string:
JObject joResponse = JObject.Parse(JsonConvert.DeserializeObject<string>(strResp))
You might have more success either using a JObject, or the alternative is to deserialize into a Dictionary, or into a known type.
var dictionary = JsonConvert.DeserializeObject<<Dictionary<string,object>>(strResp);

The problem here was the return type of the controller function. As it was returning string, the serialization to string was required to get correct result. The correct way of returning JSON is to return a JToken as explained here. So the controller needs to be changed to the following:
public JToken GetListofResourcesInSubscription(string subscriptionId)
{
return JObject.Parse(varStr);
}

RestSharp get serialized output

I am looking for a way to access the serialized result of the AddBody call.
I am using the built in RestSharp Serializer.
Example:
class Foo
{
public string FooField;
}
void SendRecord()
{
var f = new Foo();
f.FooField = "My Value";
request.AddBody(f);
// How do I get the serialized json result of the add body call without
// data? I would like to log the serialized output of the add body call to
// the database.
//Expected {"FooField":"My Value"}
var response = client.Execute(request);
}

I figured it out by finding this post.
request.Parameters.Where(p => p.Type == ParameterType.RequestBody).FirstOrDefault();

I also struggled with this (using v107 preview) and couldn't find any examples of logging the actual string sent to the server. The issue I was trying to debug was getting the right serialisation settings so the object was no use to me.
The only way I could find to get the serialized body as a string was to hook into the OnBeforeRequest event on the RestRequest:
var request = new RestRequest("/", Method.Post)
.AddHeader(KnownHeaders.ContentType, "application/json", false)
.AddJsonBody(myObj);
request.OnBeforeRequest = async (httpRequest) =>
{
var requestBodyStr = await httpRequest.Content.ReadAsStringAsync();
Trace.WriteLine($"Request body: {requestBodyStr}");
};

RestSharp itself doesn't expose the serialized request body when you pass an object to it.
There is a way to get at it though, I just posted over here:
https://stackoverflow.com/a/75537611/2509281

Right off the RestSharp homepage (http://restsharp.org/):
// execute the request
RestResponse response = client.Execute(request);
var content = response.Content; // raw content as string <~~~~~~~~~~

Deserialize Json to Object in a handler

I have a simple class:
public class site
{
public string URL { get; set; }
}
That exists within a http handler. Currently I am posting json to this handler and trying to deserialize it to get the URL out of the string. I am however having a problem with the deserialize part of it.
I have a string "jsonString" that has the json formatted like so:
[{"URL":"http://www.google.com/etc/"}]
Here is my code for the deserialize:
JavaScriptSerializer jsonSerializer = new JavaScriptSerializer();
string jsonString = String.Empty;
HttpContext.Current.Request.InputStream.Position = 0;
using (StreamReader inputStream = new StreamReader(HttpContext.Current.Request.InputStream))
{
jsonString = inputStream.ReadToEnd();
}
site currSite = new site();
currSite = jsonSerializer.Deserialize<site>(jsonString);
//set response types
HttpContext.Current.Response.ContentType = "application/json";
HttpContext.Current.Response.ContentEncoding = Encoding.UTF8;
//send response
HttpContext.Current.Response.Write(jsonSerializer.Serialize(currSite.URL));
I am then trying to send a response using currSite.URL however it is failing. What am I missing here? I am reasonably confident it is at the deserialize part because if I send a response of jsonString instead of currSite.URL it will work.

Your json string shows that it's an array, not a single entity. You should deserialize it as so:
var result = jsonSerializer.Deserialize<site[]>(jsonString);
And result[0].Url should contain what you are looking for.
Update
Adding sample code:
string json = #"[{""URL"":""http://www.google.com/etc/""}]";
JavaScriptSerializer js = new JavaScriptSerializer();
var result = js.Deserialize<site[]>(json);
Console.WriteLine(result[0].URL);
Prints:
http://www.google.com/etc/

If you're simply trying to send back the URL as the response (just the string) there's no need to serialize the value. Just pass currSite.URL to the Write method.
Otherwise, I'm guessing you should serialize the whole currSite object for the response rather than just the URL. It all depends on what kind of response the caller is expecting (which you haven't specified).

Deserialize JSON Stream with JSON.net

I recently switched from using SOAP to JSON. I now have a problem with the performance because it takes about 26 seconds to deserialize the JSON stream on my WP7 device.
Therefore I thought about using Json.net instead of DataContractJsonSerializer.
However, I was not able to find much information about this.
I use a webclient and then OpenReadAsync, so I have a Stream as e.Result.
How can I turn that stream into an object using Json.net?
Should I maybe use DownloadStringAsync instead?
This is the Code that currently works:
//string URL = ""; //Actual URL to JSON is here
WebClient client = new WebClient();
client.OpenReadCompleted += new OpenReadCompletedEventHandler(client_OpenReadCompleted);
client.OpenReadAsync(new Uri(URL, UriKind.Absolute));
And the event handler:
void client_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(JSONObject), null);
JSONObject data = serializer.ReadObject(e.Result) as JSONObject;
}
JSONObject is the response object of the service's SOAP endpoint, but both endpoints return the same data.
This works fine and I can go on and parse data just like I parsed the SOAP response, but I would like it do deserialize faster.

In order to deserialize you'll need the whole JSON. It may be better to use DownloadStringAsync and once you've received the entire JSON string, you can deserialize it.
Then in your DownloadStringCompleted you can pass in the class you want to deserialize it to. For example, if you are receiving JSON like:
{ name: "smoak", title: "super awesome" }
Then you need to create a class with those properties:
class SomeClassName
{
publc string name { get;set;}
public string title { get;set; }
}
and pass it to the JsonConvert:
var deserializedObj = JsonConvert.DeserializeObject<SomeClassName>(e.Result);
Console.WriteLine(deserializedObj.name);