Send listboxfor to controller

Question

I have a form in my view that contains a listbox. The user adds values to the listbox.

When the user pushes the \'submit\' button I want all the values in the listbox to

Answer 1

A multiple select post back an array of simple values (say [1, 4, 7] or ["Recipe 2", "Recipe 4" ] depending on the values of the selected options). You cannot bind ListBoxFor to a collection of complex objects. Your view model needs to have a property to bind to. Assuming typeof Ingredient contains properties int ID and string Name, then you view model would be something like

public class RecipeViewModel
{
  public int[] SelectedIngredients { get; set; }
  public SelectList IngredientList { get; set; }
}

Then the controller

public ActionResult Create()
{
  RecipeViewModel model = new RecipeViewModel();
  // Populate the collection of available ingredients
  model.IngredientList = new SelectList(db.Ingredients, "ID", "Name");
  // if you want to pre select some options, then: model.SelectedIngredients = new int[] { 1, 4, 7 };
  return View(model);
}

[HttpPost]
public ActionResult Create(RecipeViewModel model)
{
  // model.SelectedIngredients will contain the ID's of the selected ingredients
}

And in the view

@model RecipeViewModel
@using(Html.BeginForm())
{
  ....
  @Html.ListBoxFor(m => m.SelectedIngredients, Model.IngredientList)
  ....
}