C# Rest Service Call

C# HttpClient and HttpWebRequest can both get the job done.

The following example use Basic authentication, which requires to convert username & password into a string token and embed in the http header.

The conversion simply concatenates the username and password with colon as delimiter and convert it to ascii bytes. 

                using System.Net;

                HttpClient client = new HttpClient();

                byte[] byteArray = Encoding.ASCII.GetBytes("username:password");

                client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(byteArray));

                client.DefaultRequestHeaders.Accept.Clear();

                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("text/html"));

                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/xml"));

                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

                //Async call to the api

                HttpResponseMessage response = await client.GetAsync("http://testapi.com.au/api");               

                HttpContent content = response.Content;

                //check status code                                

                Console.WriteLine("Response StatusCode: " + (int)response.StatusCode);

                //read the string.

                string result = await content.ReadAsStringAsync();

The httpclient method use GetAsync for GET method and PostAsync for POST method.

The HttpWebRequest method is similar.

                using System.Net;

                HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://testapi.com.au/api");

                request.Method = "GET";

                String token = Convert.ToBase64String(ASCIIEncoding.ASCII.GetBytes("username:password"));

                request.Headers["Authorization"] = "Basic" + " " + token;

                HttpWebResponse response = (HttpWebResponse)request.GetResponse();

                Stream responseStream = response.GetResponseStream()

                //...read from the stream for the content

The result returned from the service call is normally Jason or Xml string. Just convert it to anything you need.