ProgramGood.Net

var db = new northwindDataContext();
IEnumerable<SelectListItem> items = db.Categories.Select(c => new SelectListItem {Value = c.CategoryID.ToString(), Text = c.CategoryName});
ViewData["CategoryID"] = items;

 

in the view:

<%= Html.DropDownList("CategoryID") %>

which is the pretty much the same as:

 

<%= Html.DropDownList("CategoryID", (IEnumerable<SelectListItem>)ViewData["Categories"]) %>

2) SelectList is tidier, and gives a couple of overloads including selected (in the case below number 3):

 

var query = db.Categories.Select(c => new {c.CategoryID , c.CategoryName});
ViewData["Categories"] = new SelectList(query.AsEnumerable(), "CategoryID", "CategoryName",3);

 

<% using (Html.BeginForm(null, null, FormMethod.Post, new { id = "TheForm" })) {%> 
<%=Html.DropDownList("CategoryID", (SelectList)ViewData["Categories"], new { onchange="this.form.submit();"})%>
<%}%>

and the product controller:

public ActionResult Index(int? categoryid)
{
    var db = new northwindDataContext();

    var query = db.Categories.Select(c => new {c.CategoryID, c.CategoryName});
    ViewData["Categories"] = new SelectList(query.AsEnumerable(), "CategoryID", "CategoryName");

    List<Product> products;
    if (categoryid == null)
        products = db.Products.ToList();
    else
        products = (from p in db.Products
                    where p.CategoryID == categoryid
                    select p).ToList();
    return View(products);
}

which gives:

 

 

The database I used was Northwind: http://www.microsoft.com/downloads/en/confirmation.aspx?familyId=06616212-0356-46a0-8da2-eebc53a68034&displayLang=en

Used LinqToSQL.

ASP.NET MVC version 1

 

Found I had to sort a generic list

 

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