ASP.NET MVC - Html.DropDownList - Value not set via ViewData.Model

Question

Have just started playing with ASP.NET MVC and have stumbled over the following situation. It feels a lot like a bug but if its not, an explanation would be appreciated :)<

Answer 1

When you have problems with invalid or null ViewData, pay attention to your controller's action.

Suppose you have a ViewData called MyList for Html.DropDownlist called MyList.

If you call ModelState.AddModelError("MyList","Please select the profession") you'll replace your ViewData list content with the this warning text.

That's also why people around internet is having null problems with ViewData on DropDownList.

The bottom line is, pay attention to your IDs on error model, they must not interfere with your html controls.