将SelectList项目列表从一个控制器传递到另一个

Question

I had used select list item in controller action and pass the select list item values to another controller action by passing in parameter but didn't get any values in another controller action

// first controller action

List<SelectListItem> dropdownItems = new List<SelectListItem>();
foreach (var item in (IEnumerable)singlecheckbox)
  {
    int Id = Convert.ToInt32(item);
    dropdownItems.AddRange(new[]{
    new SelectListItem() { Text = null, Value = Id.ToString() }});
  }
 return RedirectToAction("mergeletterttofiles123", "managefile", new { dropdownItems, SeatId = seatId });

// 2nd controller action

public ActionResult mergeletterttofiles123(List<SelectListItem> dropdownItems, int SeatId, string msg)
{
     // dropdownItems shows null( 0 count)
}

Answer 1

As an option you can store list in Session:

...........
//your code
Session["dropdownItems"]=dropdownItems;
RedirectToAction("mergeletterttofiles123", "managefile", new { SeatId = seatId });

And then:

public ActionResult mergeletterttofiles123(int SeatId, string msg)
{
    //then get it using something like
    var dropdownItems = Session["dropdownItems"] as List<SelectListItem>;
}