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MVC4 C # Filling data in view mode from database

I have a viewmodel that needs data from two person models and an address:

Models:

public class Person
{
   public int Id { get; set; }
   public string Name { get; set; }
   public int Age { get; set; }
   public int Gender { get; set; }
}

public class Address
{
   public int Id { get; set; }
   public string Street { get; set; }
   public int Zip { get; set; }
   public int PersonId {get; set; }
}

Viewmodel as such

public class PersonAddViewModel
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Street { get; set; }
}

I tried several ways to get the data in the viewmodel and pass it to the view. Several entries will be displayed.

My last method fills the view model as such:

private AppContexts db = new AppContexts();
public ActionResult ListPeople()
{
    var model = new PersonAddViewModel();
    var people = db.Persons;
    foreach(Person p in people)
    {
        Address address = db.Addresses.SingleOrDefault(a => a.PersonId == p.Id)
        model.Id = p.Id;
        model.Name = p.Name;
        model.Street = address.Street;
    }
    return View(model.ToList());
}

I get the error Address address = db ... "EntityCommandExecutionException failed to execute user code.

How can you populate a view model with multiple entries and move on to the view?

Final decision:

private AppContexts db = new AppContexts();
private AppContexts dbt = new AppContexts();
public ActionResult ListPeople()
{
    List<PersonAddViewModel> list = new List<PersonAddViewModel>();
    var people = db.Persons;
    foreach(Person p in people)
    {
        PersonAddViewModel model = new PersonAddViewModel();
        Address address = dbt.Addresses.SingleOrDefault(a => a.PersonId == p.Id)
        model.Id = p.Id;
        model.Name = p.Name;
        model.Street = address.Street;
    }
    return View(list);
}
+5
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2 answers

-, EntityCommandExecutionException . , , , , . .

-, , , , , . , Where where. :

public class Person
{
   public int Id { get; set; }
   public string Name { get; set; }
   public int Age { get; set; }
   public int Gender { get; set; }

   public virtual Address Address { get; set; }
   // or possibly, if you want more than one address per person
   public virtual ICollection<Address> Addresses { get; set; }
}

public class Address
{
   public int Id { get; set; }
   public string Street { get; set; }
   public int Zip { get; set; }
   public int PersonId { get; set; }

   public virtual Person Person { get; set; }
}

:

public ActionResult ListPeople()
{
    var model = (from p in db.Persons // .Includes("Addresses") here?
                select new PersonAddViewModel() {
                    Id = p.Id,
                    Name = p.Name,
                    Street = p.Address.Street,
                    // or if collection
                    Street2 = p.Addresses.Select(a => a.Street).FirstOrDefault()
                });

    return View(model.ToList());
}
+5

, :

public class GenericViewModel<T>
{
    public List<T> Results { get; set; }

    public GenericViewModel()
    {
        this.Results = new List<T>();
    }
}

, , :

[HttpGet]
public ActionResult GetAllPeople(GenericViewModel<People> viewModel)
{
    var query = (from x in db.People select x); // Select all people
    viewModel.Results = query.ToList();

    return View("_MyView", viewModel);
}

, :

@model NameSpace.ViewModels.GenericViewModel<NameSpace.Models.People>
+2

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