selectlist fails when accessing dataTextField

I am trying to create a Dropdownlist for a list of the following class:

public class PrimulaPositionViewModel
{
    public long Id { get; set; }
    public Dictionary<string, string> Name { get; set; }
}

and in my cshtml view i call the dropdownlist like this:

@Html.DropDownList("Position", new SelectList(Model.Positions, "Id", "Name['sv']", 
guise.PrimulaPositionId))

My issue is that "Name['sv']" doesn't get the value held in the dictionary and instead makes the program throw an error. If i were to just write Name then i would get an error but the dropdownlist simply outputs system.gen...... to represent the dictionary.

so i am wondering how i can access the Name["sv"] value when i am creating the SelectList in the view.

We usually put propertyName as dataTextField in SelectListItem. If you want to use dictionary,you can use <select></select>,and put Id and Name['sv'] into option in foreach:

<select>
        @foreach (var item in Model.Positions)
        {
            if (item.Id == guise.PrimulaPositionId)
            {
                <option id="@item.Id" selected>@item.Name["sv"]</option>
            }
            else
            {
                <option id="@item.Id">@item.Name["sv"]</option>
            }

        }
    </select>