Adding new related entities in a single action - entity-framework

Question

Every riddle has one or more questions, how can add both a Riddle and a Question to that riddle by submitting a single form?
This is RiddlesController Create action code:
public ActionResult Create(RiddleViewModel model)
{
if (ModelState.IsValid)
{
try
{
_db.Riddles.Add(new Models.Riddle
{
Name = model.Name,
Description = model.Description ,
CreationDate = DateTime.Now,
User = _db.Users.Find(User.Identity.GetUserId()),
});
_db.Questions.Add(new Models.Question
{
Body = model.FirstQuestionBody,
Answer = model.FirstQuestionAnswer,
CreationDate = DateTime.Now,
// What should I write here? or is there any better way to accomplish this?
Riddle = ?????
});
_db.SaveChanges();
return RedirectToAction("Index");
}
catch
{
return View();
}
}
return View();
}
This is Riddle model code:
public class Riddle
{
public int Id { get; set; }
public string Name { get; set; }
[MaxLength(200)]
[DataType(DataType.MultilineText)]
public string Description { get; set; }
public List<Review> Reviews { get; set; }
[Required]
public ApplicationUser User { get; set; }
public virtual List<Question> Questions { get; set; }
[Column(TypeName = "datetime2")]
public DateTime CreationDate { get; set; }
}
This is Question model code:
public class Question
{
public int Id { get; set; }
public string Body { get; set; }
public string Answer { get; set; }
public Riddle Riddle { get; set; }
[Column(TypeName ="datetime2")]
public DateTime CreationDate { get; set; }
}
This is RiddleViewModel code:
public class RiddleViewModel
{
[Required]
public string Name { get; set; }
[MaxLength(200)]
[DataType(DataType.MultilineText)]
public string Description { get; set; }
// Question properties
[DataType(DataType.MultilineText)]
public string FirstQuestionBody { get; set; }
public string FirstQuestionAnswer { get; set; }
}

Answer 1

You can try as shown below.
_db.Questions.Add(new Models.Question
{
Body = model.FirstQuestionBody,
Answer = model.FirstQuestionAnswer,
CreationDate = DateTime.Now,
Riddle = new Models.Riddle
{
Name = model.Name,
Description = model.Description ,
CreationDate = DateTime.Now,
User = _db.Users.Find(User.Identity.GetUserId()),
}
});
_db.SaveChanges();