Mexx_ Mexx_ - 1 month ago 15
ASP.NET (C#) Question

ASP.NET MVC Razor: Add empty value to a DropDownList

I tried for hours to get it work, but now I have to ask..

As read in

/942262/add-empty-value-to-a-dropdownlist-in-asp-net-mvc and
/3780614/mvc-clear-default-selected-value-of-selectlist

I want to add an empty space to dropdown lists in my ASP.NET MVC Razor WebApp with Entity Framework 5 to force the user for an input.

I followed the informations, but what happend in the View is that: http://i.stack.imgur.com/EXSgT.png

So, as you see, there is an empty space, but it isn't selected by default. Instead, my "testproject", as first value from my controller, is marked.. Not the empty space.
So where did I fail?




Thanks a lot.




My model looks like that:

[...]
using System.Web.Mvc;

public class UploadTranferContainer
{
[DisplayName("Project")]
public int ProjectID { get; set; }

public SelectList Projects { get; set; }
}


My controller fills the data in like:

UploadTranferContainer container = new UploadTranferContainer();
container.Projects = new SelectList(db.Projects.AsEnumerable(), "ProjectID", "ProjectName");


And the view unpacks my container like:

<div class="editor-label metadataLabel">
@Html.LabelFor(x => x.ProjectID)
</div>
<div class="editor-field">
@Html.DropDownListFor(x => x.ProjectID, Model.Projects, string.Empty)
</div>

Jay Jay
Answer

The selected value of the dropdown will be the value (if found) of Model.ProjectID

If you want this to appear as the first (empty) option of the select, make sure the value of ProjectID is not contained in the select list items Model.Projects