@Html.Action for Razor

Question

I am trying to create a partialview for my dropdownlistbox in my asp.net mvc 3 application. in my page I have:

@Html.Action("PopulateCombo","ComboController")

controller partialview:

public ActionResult PopulateCombo()
{
    //some code here to organise data and maybe some caching
    return ItemsForCombo;
}

Is there a better way of templating a Dropdownlistbox?

Answer 1

I would populate the data in the controller, then pass it to a model and finally use an Html.DropDownListFor . I mean, that's what MVC stands for :)

Example

(PS: it's been quite a while since I not code in c# anymore so apologies for any kind of typo)

controller.cs

Public ActionResult () 
{
    Model m = new Model(); 
    //populate data into a list
    m.Items = ...

    return View(m);
} 

model.cs

...
Public List<object> Items { get; set; }

index.cshtml

@using Model // I guess it was something like this

// I cant remember the exact order of the arguments to dropdownlistfor, so just figure it out :)
@Html.DropDownListFor (some arguments)

Answer 2

What are your requirements? Partial view could represent a control that you could re-use throughout your application. I don't think that a drop down list is a good candidate for a partial view.

If I were you and I wanted to display a drop down list, I would use an existing HTML helper.

In my controller I would store values for a drop down list in the view bag:

IList<SelectListItem> selectListItems = new List<SelectListItem>();
// Populate selectListItems
...

// Create a select list. You'll have to replace dataValueField and dataTextField with property names
SelectList mySelectList = new SelectList(selectListItems, "dataValueField", "dataTextField");

// Assume that select list contains a list of countries
ViewBag.Countries = mySelectList;

Then in your view, you can create a dropdown list with HTML helper

@Html.DropDownListFor(m => m.CountryId, (SelectList) ViewBag.Countries);

I wrote this in notepad, so there might be syntax errors.