Linq MVC 2 TryUpdateModel nullable bool - validation

Question

I have been having an issue with updating a nullable bool value using TryUpdateModel. I have a template created to handle the values as so:
<%# Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<System.Boolean?>" %>
<% if (ViewData.ModelMetadata.IsNullableValueType) { %>
<%= Html.DropDownListFor(model => model, new SelectListItem[] { new SelectListItem() { Text = "", Value = "null"},new SelectListItem() { Text = "Yes", Value = "true"}, new SelectListItem() { Text = "No", Value = "false" }})%>
<% } else { %>
<%= Html.CheckBoxFor(model => model.Value)%>
<% } %>
My View looks like this:
<%=Html.EditorFor(model => model.TestField) %> //which looks/acts correctly
The SQL Server Database types are also defined correctly as a nullable bit.
My Code is straight forward:
var so = new SomeObject();
if (ModelState.IsValid)
{
//gets to here
if (TryUpdateModel(so))
{
//never gets here
}
}
The Error reported for ModelState on that field is: "The value 'null' is not valid for TestField."
This seems pretty straight forward, but I wasn't able to find anything on this. Any help would be greatly appreciated.
Cheers,
Brian

Answer 1

Since nobody has answered my question, I will put my workaround up. It's not super elegant, but it works. If I wanted it to be pretty, it'd be in a pink font. ;)
Basically I had to load "so" (someObject) manually using the form Collection like so...
var so = new SomeObject();
if (ModelState.IsValid)
{
so.WasItFound = StringToNullBool(form["WasItFound"]);
so.WhereWasItFound = form["WhereWasItFound"];
//fill in the rest of the properties using the form Collection...
}
private bool? StringToNullBool(string s)
{
if (s != "null")
return Convert.ToBoolean(s);
else
return null;
}