C-sharp Sample

using System;
using System.Text;
using System.Net;
using System.IO;

namespace SampleODataClient
{
    class Program
    {
        static void Main(string[] args)
        {
            // You can test this app using the following tenant which doesn't 
            // require user credentials.
            // To test on your tenant, replace the URL with your own tenant URL
            // and provide user credential
            string URL = "https://odatac4ctrial.hana.ondemand.com/proxy";
            var username = "username";
            var password = "password";

            var authHeader = "Basic " + Convert.ToBase64String(Encoding.Default.GetBytes(username + ":" + password));
            var cookieContainer = new CookieContainer();
            // Get request for reading the list of collections
            HttpWebRequest request = (HttpWebRequest)(WebRequest.Create(URL + "/sap/c4c/odata/v1/c4codata/"));
            // Share cookies between the requests
            request.CookieContainer = cookieContainer;
            // Set auth header
            request.Headers.Add("Authorization", authHeader);
            // Set header to fetch a CSRF token to be used in modifying requests
            request.Headers.Add("x-csrf-token", "fetch");
            // Set accept header to get the data in JSON. Default response format is XML
            request.Accept = "application/json";
            // Get the response.  
            HttpWebResponse response = (HttpWebResponse)(request.GetResponse());
            // Get the stream containing content returned by the server.  
            Stream dataStream = response.GetResponseStream();
            // Open the stream using a StreamReader for easy access.  
            StreamReader reader = new StreamReader(dataStream);
            // Read the content.  
            string responseFromServer = reader.ReadToEnd();
            // Display the content.  
            Console.WriteLine("JSON Response to HTTP GET to read service collections");
            Console.WriteLine("=====================================================");
            Console.WriteLine("Status:"+response.StatusDescription+"\n");
            Console.WriteLine(response.Headers.ToString());
            Console.WriteLine(responseFromServer+"\n");
            // Get x-csrf-token
            string x_csrf_token = response.Headers["x-csrf-token"];
            // Clean up the streams and the response.  
            response.Close();

            // Create a request using a URL that can receive a post.   
            request = (HttpWebRequest)(WebRequest.Create(URL + "/sap/c4c/odata/v1/c4codata/AccountCollection"));
            // Set the Method property of the request to POST.  
            request.Method = "POST";
            // Create POST data and convert it to a byte array.  
            // Create a new account
            string postData = "{\"AccountName\":\"Sample Customer\",\"RoleCode\":\"CRM000\",\"RoleCodeText\": \"Customer\"}";
            byte[] byteArray = Encoding.UTF8.GetBytes(postData);
            // Set headers
            request.CookieContainer = cookieContainer;
            request.Headers.Add("Authorization", authHeader);
            request.Headers.Add("X-CSRF-Token", x_csrf_token);
            request.Accept = "application/json";
            // Set the ContentType to JSON. Default content-type is XML 
            request.ContentType = "application/json";
            request.ContentLength = byteArray.Length;
            // Get the request stream.  
            dataStream = request.GetRequestStream();
            // Write the data to the request stream.  
            dataStream.Write(byteArray, 0, byteArray.Length);
            // Close the Stream object.  
            dataStream.Close();
            // Get the response.  
            response = (HttpWebResponse)(request.GetResponse());
            // Get the stream containing content returned by the server.  
            dataStream = response.GetResponseStream();
            // Open the stream using a StreamReader for easy access.  
            reader = new StreamReader(dataStream);
            // Read the content.  
            responseFromServer = reader.ReadToEnd();
            // Display the content.  
            Console.WriteLine("JSON Response to HTTP POST to create a new Account");
            Console.WriteLine("==================================================");
            Console.WriteLine("Status:" + response.StatusDescription + "\n");
            Console.WriteLine(response.Headers.ToString());
            Console.WriteLine(responseFromServer + "\n");
            Console.WriteLine("\nPress any enter to continue...");
            // Clean up the streams.  
            reader.Close();
            dataStream.Close();
            response.Close();
            Console.ReadKey();
        }
    }
}