Asp.Net Mvc Checkbox list

Question

I'm implementing check box list in MVC, although I succeed to get the desired result, I have a doubt in my approach:

public class AdditionalServicesModel
{
    public IList<SelectListItem> AdditionalServices { get; set; }
}

=========================================================================

public class HomeController : Controller
{
    //
    // GET: /Home/

    public ActionResult Index()
    {
        AdditionalServicesModel objAdditionalServicesModel = new AdditionalServicesModel();

        List<SelectListItem> services = new List<SelectListItem>();
        services.Add(new SelectListItem { Text = "service-1", Value = "1", Selected=false });
        services.Add(new SelectListItem { Text = "service-2", Value = "2", Selected=false });
        services.Add(new SelectListItem { Text = "service-3", Value = "3", Selected=false });
        objAdditionalServicesModel.AdditionalServices = services;

        return View(objAdditionalServicesModel);
    }

    [HttpPost]
    public ActionResult Index(AdditionalServicesModel result)
    {
        return RedirectToAction("Thanks", "Home");
    }

    public ActionResult Thanks()
    {
        return View();
    }
}

=========================================================================

@model checkboxes.Models.AdditionalServicesModel
@{
    ViewBag.Title = "Index";
    Layout = null;
}


@using (Html.BeginForm("Index", "Home", FormMethod.Post))
{
    for (int i = 0; i < Model.AdditionalServices.Count; i++)
    {        
        <ul>
            <li>
                @Html.CheckBoxFor(m=>Model.AdditionalServices[i].Selected, new { id = "Chk-" + i})
                @Html.Label(Model.AdditionalServices[i].Text, new { @for = "Chk-" + i })
                @Html.HiddenFor(m => Model.AdditionalServices[i].Text)
                @Html.HiddenFor(m=> Model.AdditionalServices[i].Value)
            </li>
        </ul>
    }
    <input type="submit" value="POST to Controller" />
}

1) For one checkbox I should create 2 additional hidden fields. Is there a better approach? I feel like it just wrong to make all this long way just to send checkboxes values + names, It would be much easier to collect its values with javascript and send it via Json, but then I will not have an unobtrusive validation...

2) I send all check boxes while I need to send only selected boxes. Is there a way to do it with forms post?

Answer 1

Create a custom 'services check box item' class (reusable), and make a list or enumerable of them as a property in your AdditionalServicesModel. Also, its probably a better idea to create a constructor of the model so you don't have to assign the model properties inside the controller.

public class ServicesItem
{
     public bool Selected { get; set; }
     public string Value { get; set; }
     public string Text { get; set; }
}

public class AdditionalServicesModel
{
    public AdditionalServicesModel(IList<ServicesItem> items){
         this.AdditionalServices = items;
    }

    public IList<ServicesItem> AdditionalServices { get; set; }
}

Create a custom editor template for Additional Services, to easily reference in your view (you don't have to add a hidden for the text, as only the value and selected properties will be default binded back to the model:

  @Html.CheckBoxFor(m => Selected)
  @Html.LabelFor(m => Text)
  @Html.HiddenFor(m => Value)

Then pop the editor template into your view (let MVC.net do its magic - have a look at the markup to see what it does):

@Html.EditorFor(m => m.AdditionalServices)

Then inspect the automatically bound values in your controller:

    public class HomeController : Controller
    {
        public ActionResult Index()
        {
            List<SelectListItem> services = new List<SelectListItem>();
            services.Add(new SelectListItem { Text = "service-1", Value = "1", Selected=false });
            services.Add(new SelectListItem { Text = "service-2", Value = "2", Selected=false });
            services.Add(new SelectListItem { Text = "service-3", Value = "3", Selected=false });

            return View(new AdditionalServicesModel(services));
        }

    [HttpPost]
    public ActionResult Index(AdditionalServicesModel result)
    {
         var selectedServicesList = result.AdditionalServices.Where(s => s.Selected);
         return RedirectToAction("Thanks", "Home");
    }
}