How to pass multiselect list's selected Items back to controller?

Question

I am developing a MVC application which contains the multiselect dropdown list. I want to get the ID\'s of multiple selected items of the drop down.

I have the code

Answer 1

Using a wrapper model with a property to bind the selected customers to works (I tried it):

Wrapper Model:

public class CustomerList
{
    public List<Customer> Customers { get; set; }
    public List<int> SelectedIDs { get; set; }
}

Controller:

        [HttpGet]
        public ActionResult DisplayCustomer()
        {
            Customer oCustomer = new Customer();
            List<Customer> CustomersList = new List<Customer>();
            CustomersList.Add(new Customer() { ID = 1, Name = "TestCustomer1", Amt = 123 });
            CustomersList.Add(new Customer() { ID = 2, Name = "TestCustomer2", Amt = 234 });
            CustomersList.Add(new Customer() { ID = 3, Name = "TestCustomer3", Amt = 324 });
            ViewBag.CustList = CustomersList;
            return View(new CustomerList() { Customers = CustomersList }); 

        }

        [HttpPost]
        public void DisplayCustomer(List<int> selectedIds)
        {
            // do something with the id list
        }

View:

@model MvcApplication2.Models.CustomerList

@using (Html.BeginForm(@Model.SelectedIDs))
{
    @Html.ListBoxFor(m => m.SelectedIDs, new MultiSelectList(@Model.Customers, "ID", "Name", @Model.SelectedIDs))
    <input type="submit" value="save" />
}

You need something to bind your selection to and send it back to the controller.