/Undelete

using System;
using System.Net;
using System.Net.Http;
using System.Text;

namespace REST.Test
{
    class Program
    {
        static void Main(string[] args)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri("https://restapi.tpondemand.com/api/v1/");
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

            // undelete Project ID#229
            string query = "undelete";
            HttpContent payload = new StringContent("{Id:229,EntityType:'Project'}", Encoding.UTF8, "application/json");

            //using access token generated at Personal Details page (Access Tokens tab)
            query += "?access_token=MTpoUmx4WW1LTzF6dlkvbUN1dTZIclVBUFQyQ1Z0MkN6YnF6OHBETmRZN2kwPQ==";
            Console.WriteLine("Posting to " + query);

            HttpResponseMessage response = client.PostAsync(query, payload).Result;
            if (response.IsSuccessStatusCode)
            {
                Console.WriteLine(response.Content.ReadAsStringAsync().Result);
            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }
        }
    }
}

using System;
using System.Net;
using System.Net.Http;
using System.Text;

namespace REST.Test
{
    class Program
    {
        static void Main(string[] args)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri("https://restapi.tpondemand.com/api/v1/");
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

            // undelete Project ID#229
            string query = "undelete";
            HttpContent payload = new StringContent("{Id:229,EntityType:'Project'}", Encoding.UTF8, "application/json");

            //using access token generated at Personal Details page (Access Tokens tab)
            query += "?access_token=MTpoUmx4WW1LTzF6dlkvbUN1dTZIclVBUFQyQ1Z0MkN6YnF6OHBETmRZN2kwPQ==";
            Console.WriteLine("Posting to " + query);

            HttpResponseMessage response = client.PostAsync(query, payload).Result;
            if (response.IsSuccessStatusCode)
            {
                Console.WriteLine(response.Content.ReadAsStringAsync().Result);
            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }
        }
    }
}

using System;
using System.Net;
using System.Net.Http;
using System.Text;

namespace REST.Test
{
    class Program
    {
        static void Main(string[] args)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri("https://restapi.tpondemand.com/api/v1/");
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

            // undelete Project ID#229
            string query = "undelete";
            HttpContent payload = new StringContent("{Id:229,EntityType:'Project'}", Encoding.UTF8, "application/json");

            //using basic authentication (here 'John' is login and '123' is password)
            string authentication = Convert.ToBase64String(Encoding.ASCII.GetBytes("admin:admin"));
            client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", authentication);
            Console.WriteLine("Posting to " + query);

            HttpResponseMessage response = client.PostAsync(query, payload).Result;
            if (response.IsSuccessStatusCode)
            {
                Console.WriteLine(response.Content.ReadAsStringAsync().Result);
            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }
        }
    }
}

using System;
using System.Net;
using System.Net.Http;
using System.Text;

namespace REST.Test
{
    class Program
    {
        static void Main(string[] args)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri("https://restapi.tpondemand.com/api/v1/");
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

            // undelete Project ID#229
            string query = "undelete";
            HttpContent payload = new StringContent("{Id:229,EntityType:'Project'}", Encoding.UTF8, "application/json");

            //using no authentication will result in 401 Unauthorized response
            Console.WriteLine("Posting to " + query);

            HttpResponseMessage response = client.PostAsync(query, payload).Result;
            if (response.IsSuccessStatusCode)
            {
                Console.WriteLine(response.Content.ReadAsStringAsync().Result);
            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }
        }
    }
}