MVC View nullable Date field formatting
@(item.CreatedByDt.HasValue ? item.CreatedByDt.Value.ToString("MM/dd/yyyy") : "--/--/----")
You can replace the display string for when your date is null with what you want.
If you don't know if it will be null or not...
@string.Format("{0:MM/dd/yyyy}", item.CreatedByDt)