public ActionResult Index(SelectListItemViewModel m)
{
// Get all the animals and continents that we want pass to the selectlist
// and assign them to the corresponding properties
var animals = Help.GetAnimals();
var continents = Help.GetContinents();
// Construct the SelectListItem objects
var continentList = continents.Select(c => new SelectListItem { Value = c.ContinentID.ToString(), Text = c.Name, Selected = m.SelectedContinentID == c.ContinentID }).ToList();
var animalList = animals.Select(a => new SelectListItem { Value = a.AnimalID.ToString(), Text = a.Name, Selected = m.SelectedAnimalsIDs.Contains(a.AnimalID) });
// Re-populate animal and continent lists:
m.ContinentList = continentList;
m.AnimalList = animalList;
// get the names of selected continent and animals
m.ContinentName = continents.Where(c => c.ContinentID == m.SelectedContinentID).FirstOrDefault().Name;
m.AnimalNames = new List<string>();
foreach (var a in animals)
{
if (m.SelectedAnimalsIDs.Contains(a.AnimalID))
{
m.AnimalNames.Add(a.Name);
}
}
return View(m);
}
public ActionResult Index()
{
// Get all the animals and continents that we want pass to the selectlist
// and assign them to the corresponding properties
var animals = Help.GetAnimals();
var continents = Help.GetContinents();
// Preselected items
var selectedAnimalIDs = new int[] { 2, 5, 8 };
var selectedContinentID = 4;
// Construct the SelectListItem objects
var continentList = continents.Select(c => new SelectListItem { Value = c.ContinentID.ToString(), Text = c.Name, Selected = c.ContinentID == selectedContinentID ? true : false }).ToList();
var animalList = animals.Select(a => new SelectListItem { Value = a.AnimalID.ToString(), Text = a.Name, Selected = selectedAnimalIDs.Contains(a.AnimalID) });
// Construct the view model that we want to pass to the view
var viewModel = new SelectListItemViewModel
{
PageTitle = "Using a collection of SelectListItems as view model property",
// The view's Razor helper will receive a collection of SelectListItem object.
// The value of properties of each select list item object are set
AnimalList = animalList,
ContinentList = continentList,
OptionLabel = "*** Please select a continent! ***",
// It can be null (default value), so no animals will be preselected.
// If you assign a value, animals with the ID of those numbers will be preselected
SelectedAnimalsIDs = selectedAnimalIDs,
// It can be 0 (default value), so no continent will be preselected
// If you assign a value, continent with that ID will be preselected
SelectedContinentID = 4,
// Names of the continent and animals before submission.
// If using default value (null), check for null in the view
ContinentName = string.Empty,
AnimalNames = new List<string>()
};
return View(viewModel);
}
