How do you create a dropdownlist from an enum in ASP.NET MVC?

Question

I\'m trying to use the Html.DropDownList extension method but can\'t figure out how to use it with an enumeration.

Let\'s say I have an enumeration like

Answer 1

Well I'm really late to the party, but for what it is worth, I have blogged about this very subject whereby I create a EnumHelper class that enables very easy transformation.

http://jnye.co/Posts/4/creating-a-dropdown-list-from-an-enum-in-mvc-and-c%23

In your controller:

//If you don't have an enum value use the type
ViewBag.DropDownList = EnumHelper.SelectListFor();

//If you do have an enum value use the value (the value will be marked as selected)    
ViewBag.DropDownList = EnumHelper.SelectListFor(MyEnum.MyEnumValue);

In your View:

@Html.DropDownList("DropDownList")
@* OR *@
@Html.DropDownListFor(m => m.Property, ViewBag.DropDownList as SelectList, null)

The helper class:

public static class EnumHelper
{
    // Get the value of the description attribute if the   
    // enum has one, otherwise use the value.  
    public static string GetDescription(this TEnum value)
    {
        var fi = value.GetType().GetField(value.ToString());

        if (fi != null)
        {
            var attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);

            if (attributes.Length > 0)
            {
                return attributes[0].Description;
            }
        }

        return value.ToString();
    }

    /// 

    /// Build a select list for an enum
    /// 
    public static SelectList SelectListFor() where T : struct
    {
        Type t = typeof(T);
        return !t.IsEnum ? null
                         : new SelectList(BuildSelectListItems(t), "Value", "Text");
    }

    /// 

    /// Build a select list for an enum with a particular value selected 
    /// 
    public static SelectList SelectListFor(T selected) where T : struct
    {
        Type t = typeof(T);
        return !t.IsEnum ? null
                         : new SelectList(BuildSelectListItems(t), "Text", "Value", selected.ToString());
    }

    private static IEnumerable BuildSelectListItems(Type t)
    {
        return Enum.GetValues(t)
                   .Cast()
                   .Select(e => new SelectListItem { Value = e.ToString(), Text = e.GetDescription() });
    }
}