MVC - Set selected value of SelectList

Question

How can I set the selectedvalue property of a SelectList after it was instantiated without a selectedvalue;

SelectList selectList = new SelectList(items, \"I         


        

Answer 1

I wanted the dropdown to select the matching value of the id in the action method. The trick is to set the Selected property when creating the SelectListItem Collection. It would not work any other way, perhaps I missed something but in end, it is more elegant in my option.

You can write any method that returns a boolean to set the Selected value based on your requirements, in my case I used the existing Equal Method

public ActionResult History(long id)
        {
            var app = new AppLogic();
            var historyVM = new ActivityHistoryViewModel();

            historyVM.ProcessHistory = app.GetActivity(id);
            historyVM.Process = app.GetProcess(id);
            var processlist = app.GetProcessList();

            historyVM.ProcessList = from process in processlist
                                    select new SelectListItem
                                    {
                                        Text = process.ProcessName,
                                        Value = process.ID.ToString(),
                                        Selected = long.Equals(process.ID, id)                                    

                                    };

            var listitems = new List();

            return View(historyVM);
        }