Cannot run a restfull server in a ASP.Net without MVC

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WebAPI

ASP.NET4

I'm trying to run a simple restfull server in a simple asp.net application without the mvc(following this tutorial : http://www.codeproject.com/Articles/769671/Web-API-without-MVC (which will trun into a online portal).

here is my class :

public class Foods
{
public string FoodName { get; set; }
public string Price { get; set; }
public string Type { get; set; }
public string Content { get; set; }
}

and here is my controller:

public class FoodController : ApiController
{
public List<Foods> _productList;

public List<Foods> GetProductList()
{
    _productList = new List<Foods>{
       new Foods{FoodName= "pizza",Content= "bread cheese",Type="Main",Price="100"},
       new Foods{FoodName= "rice",Content= "rice and ...",Type="Main",Price="100"}
    };
    return _productList;
}
 }

and here is my asp.net page code(it is simple nothing to show):

public partial class _Default : System.Web.UI.Page
{
 protected void Page_Load(object sender, EventArgs e)
  {

    var config = new HttpSelfHostConfiguration("http://localhost:8080/");
    config.Routes.MapHttpRoute(
        "API Default", "api/{controller}/{id}",
        new { id = System.Web.Http.RouteParameter.Optional });

    using (HttpSelfHostServer server = new HttpSelfHostServer(config))
    {
        server.OpenAsync().Wait();
    }
}
}

when i run it there is no error and the blank page is shown

and here is the client which is a simple c# form with a list box and a button:

private void button1_Click(object sender, EventArgs e)
   {
       HttpClient client = new HttpClient();
       client.BaseAddress = new Uri("http://localhost:8080/");
       client.DefaultRequestHeaders.Accept.Add(
          new MediaTypeWithQualityHeaderValue("application/json"));
       try
       {
           HttpResponseMessage response = client.GetAsync("api/foods").Result;
           if (response.IsSuccessStatusCode)
           {
               // Parse the response body. Blocking!
               var foods = response.Content.ReadAsAsync<IEnumerable<Foods>>().Result;
               foreach (Foods food in foods)
               {
                   string foodinfo = food.FoodName + "   " + food.Content + "    " + food.Type + "    " + food.Price;
                   listBox1.Items.Add(foodinfo);
               }
           }
       }
       catch (Exception ex)
       {
           textBox1.Text = ex.ToString();
       }
   }

but when i run the client and click the button i get this error:
Object reference not set to an instance of an object.
and the page i saying source is not available