EditUserViewModel needs a DropDownListFor() - asp.net-mvc

Question

Right now I have added a Region to the ApplicationUser model in Identity 2.0
On the UsersAdmin view, Edit action, I have the following stock code to display/edit the Region of the User:
<div class="form-group">
#Html.LabelFor(model => model.Region, new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.TextBoxFor(m => m.Region, new { #class = "form-control" })
</div>
</div>
How do I make that TextBox into a DropDownList that allows the user to choose from a list of Region names where Regions is part of ApplicationDbContext?
public class Region
{
[Key]
public Guid ID { get; set; }
public string Name { get; set; }
public Company Company { get; set; }
public Region()
{
this.ID = Guid.NewGuid();
}
}

Answer 1

You could use a view model. In order to render a dropdown you need 2 properties in your view model: a scalar property to hold the selected value and a collection property to represent the list of possible values to be displayed:
public class MyViewModel
{
public Guid SelectedRegionID { get; set; }
public IEnumerable<SelectListItem> Regions { get; set; }
}
That your controller action will populate and pass to the view:
public ActionResult Index()
{
var viewModel = new MyViewModel();
viewModel.Regions = db.Regions.ToList().Select(x => new SelectListItem
{
Value = x.ID.ToString(),
Text = x.Name,
});
return View(viewModel);
}
and in the corresponding strongly typed view you could use the DropDownListFor helper:
#model MyViewModel
<div class="form-group">
#Html.LabelFor(model => model.Region, new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.DropDownListFor(m => m.SelectedRegionID, Model.Regions, new { #class = "form-control" })
</div>
</div>