In this article I will explain with an example, how to call (consume) Third Party REST API in ASP.Net Core MVC.
The Third Party REST API will be called using HttpClient class in ASP.Net Core MVC.
Note: For beginners in ASP.Net MVC Core, please refer my article ASP.Net MVC Core Hello World Tutorial with Sample Program example.
The ASPSnippets Test REST API
This article uses the following REST API hosted on GitHub.
The JSON string returned from the API
The following JSON string is returned from the ASPSnippets Test API.
      "Name":"John Hammond",
      "Country":"United States"
      "Name":"Mudassar Khan",
      "Name":"Suzanne Mathews",
      "Name":"Robert Schidner",
The Model class consists of following properties.
public class CustomerModel
    public string CustomerId { get; set; }
    public string Name { get; set; }
    public string Country { get; set; }
You will need to import the following namespaces.
using System.Net;
using System.Net.Http;
using Newtonsoft.Json;
The Controller consists of the following Action method.
Action method for handling GET operation
Inside this Action method, first the Security Protocol is set.
Note: SecurityProtocol needs to be set to TLS 1.2 (3072) in order to call an API.
Then the API is called using HttpClient and the JSON string is downloaded and deserialized to Generic List collection of CustomerModel class objects.
Finally, the Generic List collection of CustomerModel class objects is returned.
public class HomeController : Controller
    public IActionResult Index()
        //Setting TLS 1.2 protocol
        ServicePointManager.Expect100Continue = true;
        ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
        //Fetch the JSON string from URL.
        List<CustomerModel> customers = new List<CustomerModel>();
        string apiUrl = "";
        HttpClient client = new HttpClient();
        HttpResponseMessage response = client.GetAsync(apiUrl).Result;
        if (response.IsSuccessStatusCode)
            customers = JsonConvert.DeserializeObject<List<CustomerModel>>(response.Content.ReadAsStringAsync().Result);
        //Return the Deserialized JSON object.
        return Json(customers);
Call (Consume) Third Party API in ASP.Net Core