title: How to call async Task using the .Net framework v3.5
body: <p>How to call async Task Framework 3.5 please help me. I am calling this method in my 3.5 framework project its shows an error.any alternet way post json data using Framework 3.5 Here's my code:</p>
  
  <pre><code>public async void APIPushStatusDriverPostion(string direction,string carColor,string supplier_company,string SupplierAccountId,string Karho_Ref,string booking_id,string vehicale_type, string vehicle_id, string vehicle_plate, double latitude, double longitude, string carModel, string status, string driver_id, string driver_phone, string driver_first_name, string driver_last_name)
  {
      APIKarhoBookingProperties objbooking = new APIKarhoBookingProperties();
      objbooking.vehicle.vehicle_type   = vehicale_type;
      objbooking.vehicle.vehicle_id     =    vehicle_id;
      objbooking.vehicle.vehicle_plate  = vehicle_plate;
      objbooking.vehicle.latitude       =   latitude;
      objbooking.vehicle.longitude      =    longitude;
      objbooking.vehicle.eta_minutes    = "null";
      objbooking.vehicle.make           = "null";
      objbooking.vehicle.model = carModel;
      objbooking.vehicle.color = carColor;
      objbooking.vehicle.status = status;
      objbooking.vehicle.driver_id = driver_id;
      objbooking.vehicle.driver_phone = driver_phone;
      objbooking.vehicle.driver_phone = driver_first_name;
      objbooking.vehicle.driver_last_name = driver_last_name;          
  
      var json = JsonConvert.SerializeObject(objbooking);
      using (var response = await httpClient.PostAsync("{supplier_id}/availability?version=2", json))
      {
          string responseData = await response.Content.ReadAsStringAsync();
      }
  
  }
  </code></pre>