Dropdown in MVC

Question

In my MVC application, I need to add a dropdown that would show a list of domain names.

I already have a ViewModel that contains multiple properties. I am not sure w

Answer 1

1) Add a new property to my ViewModel? What should be the type? List?

You need 2 properties to be more precise: an IEnumerable to hold all the available options and a scalar property to hold the selected value

2) Define a method that populates the above property with values.

Yes.

3) Use that property in the View? Use HTML.DropdownFor?

No, not in the view. The view doesn't call any methods. A view works with the view model. It is the responsibility of the controller to pass a properly filled view model to the view.

So for example:

public class MyViewModel
{
    public string SelectedValue { get; set; }
    public IEnumerable Values { get; set; }

    ... some other properties that your view might need
}

and then a controller action that will populate this view model:

public ActionResult Index()
{
    var model = new MyViewModel();
    model.Values = new[]
    {
        new SelectListItem { Value = "1", Text = "item 1" },
        new SelectListItem { Value = "2", Text = "item 2" },
        new SelectListItem { Value = "3", Text = "item 3" },
    };
    return View(model);
}

and finally the strongly typed view in which you will display the dropdown list:

@model MyViewModel
@Html.DropDownListFor(x => x.SelectedValue, Model.Values)

---

UPDATE:

According to your updated question you are have an IEnumerable property on your view model to which you are trying to assign a value of type IEnumerable which obviously is impossible. You could convert this to an IEnumerable like this:

var domains = FetchAllDomains().Select(d => new SelectListItem
{
    Value = d.DomainName,
    Text = d.DomainName
});
return new EmailModel { DomainList = domains };