public void NewRucksack([FromBody] RucksackDataRequest value) { if (value == null || !ModelState.IsValid) { Debug.WriteLine("POST get bad value"); } using (ApplicationContext db = new ApplicationContext()) { Rucksack NewRucksack = new Rucksack { Name = value.NameRucksack, Weight = value.WeightRucksack, Cost = 0, Status = false }; db.Rucksacks.Add(NewRucksack); db.SaveChanges(); foreach (ThingDataRequest thing in value.Things) { Thing NewThing = new Thing { Name = thing.Name, Weight = thing.Weight, Cost = thing.Cost, Put = false, Rucksack = NewRucksack }; db.Things.AddRange(new List <Thing> { NewThing }); } db.SaveChanges(); MainThread.CreateThread(NewRucksack.Id); } }