Question

I have a model class called House:

public class House
{
    public House()
    {
        Residents = new List<Resident>();
    }

    public virtual string Name { get; set; }     
    ...  
    public virtual IList<Resident> Residents{ get; set; }
}

public class Resident
{
    public virtual string Name { get; set; }
    public virtual int Age{ get; set; }
    public virtual House House { get; set; }
}

So, in my view Create (House), I need to add Residents . So I added a button “Add Resident”, that opens a JQuery UI Modal with Create(Resident) and when the user click Confirm, the Modal closes and my Resident´s grid refresh…

My problem here is where I save that list … I did that using Session… But I´d like to do that without Session…

What I´ve done (My House Controller):

  [HttpGet]
  public ActionResult AddResident(Resident resident)  //Called when user confirms modal Resident
  {
      Residents.Add(resident);

      return PartialView("_Residents", Residents);
  }

  public Collection<Resident> Residents
  {
      get
      {
          if (Session["Residents"] == null)
          {
              var _lista = new Collection<Resident>();

              Session["Residents"] = _lista;
              return _lista;
          }
          return (Collection<Resident>)Session["Residents"];
      }
      set { Session["Residents"] = value; }
  }

So, what´s the right way to do that kind of scenario without session?

Thanks

Answer 1

Although it stil uses the Session behind the scene, TempData is the way to go when you want to persist data across actions calls.

An action method can store data in the controller’s TempDataDictionary object before it calls the controller’s RedirectToAction method to invoke the next action. The TempData property value is stored in session state.

The good part is that the session will be automatically cleared after your read (in your grid refresh method). It’s really what it means “temporary data”.

Here’s a sample of code with TempData:

public ActionResult AddResident(Resident resident)
{
    IList<Resident> residents = PeristResident(resident);
    return PartialView("_Residents", residents);
}

private IList<Resident> PeristResident(Resident resident)
{
    IList<Resident> residents = Residents; // this operation can empty TempData by reading it
    residents.Add(resident);
    Residents = residents; // so we persists collection after read
    return residents;
}

private IList<Resident> Residents
{
    get
    {
        object results;
        if (TempData.TryGetValue("Residents", out results) == false)
        {
            var list = new List<Resident>();
            return list;
        }
        return (IList<Resident>)results;

    }
    set { TempData["Residents"] = value; }
}