populating dropdown list

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C#

ASP.NET

SQL

LINQ

MVC

i am populating DropDown from database but now i want pre selected value for specific user, e.g. DropDown shows names of Departments, and User 5 works in Operations departments so i enter as UserID 5 then it should show preselected Department in DropDown

Code:

Controller:

var ShiftNames = (from n in DataContext.AtdShifts select new { n.ShiftId, n.ShiftName }).Distinct();
                ViewData["ShiftId"] = new SelectList(ShiftNames, "ShiftId", "ShiftName");

View:

<label id="lblShift" class="editEmp_label">Shift</label>
  @Html.DropDownList("ShiftId", "Select Shift")

I am suing Linq to sql, MVC 3 C#