RestSharp JSON Parameter Posting

I am trying to make a very basic REST call to my MVC 3 API and the parameters I pass in are not binding to the action method.

Client

var request = new RestRequest(Method.POST);

request.Resource = "Api/Score";
request.RequestFormat = DataFormat.Json;
        
request.AddBody(request.JsonSerializer.Serialize(new { A = "foo", B = "bar" }));
        
RestResponse response = client.Execute(request);
Console.WriteLine(response.Content);

Server

public class ScoreInputModel
{
   public string A { get; set; }
   public string B { get; set; }
}

// Api/Score
public JsonResult Score(ScoreInputModel input)
{
   // input.A and input.B are empty when called with RestSharp
}

Am I missing something here?

You don't have to serialize the body yourself. Just do

request.RequestFormat = DataFormat.Json;
request.AddJsonBody(new { A = "foo", B = "bar" }); // Anonymous type object is converted to Json body

If you just want POST params instead (which would still map to your model and is a lot more efficient since there's no serialization to JSON) do this:

request.AddParameter("A", "foo");
request.AddParameter("B", "bar");

In the current version of RestSharp (105.2.3.0) you can add a JSON object to the request body with:

request.AddJsonBody(new { A = "foo", B = "bar" });

This method sets content type to application/json and serializes the object to a JSON string.

This is what worked for me, for my case it was a post for login request :

var client = new RestClient("http://www.example.com/1/2");
var request = new RestRequest();
 
request.Method = Method.POST;
request.AddHeader("Accept", "application/json");
request.Parameters.Clear();
request.AddParameter("application/json", body , ParameterType.RequestBody);
 
var response = client.Execute(request);
var content = response.Content; // raw content as string  

body :

{
  "userId":"[email protected]" ,
  "password":"welcome" 
}

Hope this will help someone. It worked for me -

RestClient client = new RestClient("http://www.example.com/");
RestRequest request = new RestRequest("login", Method.POST);
request.AddHeader("Accept", "application/json");
var body = new
{
    Host = "host_environment",
    Username = "UserID",
    Password = "Password"
};
request.AddJsonBody(body);

var response = client.Execute(request).Content;

If you have a List of objects, you can serialize them to JSON as follow:

List<MyObjectClass> listOfObjects = new List<MyObjectClass>();

And then use addParameter:

requestREST.AddParameter("myAssocKey", JsonConvert.SerializeObject(listOfObjects));

And you wil need to set the request format to JSON:

requestREST.RequestFormat = DataFormat.Json;

You might need to Deserialize your anonymous JSON type from the request body.

var jsonBody = HttpContext.Request.Content.ReadAsStringAsync().Result;
ScoreInputModel myDeserializedClass = JsonConvert.DeserializeObject<ScoreInputModel>(jsonBody);

Here is complete console working application code. Please install RestSharp package.

using RestSharp;
using System;

namespace RESTSharpClient
{
    class Program
    {
        static void Main(string[] args)
        {
        string url = "https://abc.example.com/";
        string jsonString = "{" +
                "\"auth\": {" +
                    "\"type\" : \"basic\"," +
                    "\"password\": \"@P&p@y_10364\"," +
                    "\"username\": \"prop_apiuser\"" +
                "}," +
                "\"requestId\" : 15," +
                "\"method\": {" +
                    "\"name\": \"getProperties\"," +
                    "\"params\": {" +
                        "\"showAllStatus\" : \"0\"" +
                    "}" +
                "}" +
            "}";

        IRestClient client = new RestClient(url);
        IRestRequest request = new RestRequest("api/properties", Method.POST, DataFormat.Json);
        request.AddHeader("Content-Type", "application/json; CHARSET=UTF-8");
        request.AddJsonBody(jsonString);

        var response = client.Execute(request);
        Console.WriteLine(response.Content);
        //TODO: do what you want to do with response.
    }
  }
}