将SelectListItem转换为IEnumerable列表

Question

I am trying to pass a SelectListItem to a view. This checkbok list will be viewable within the view in a JavaScript dialog box with date ranges.

From the following code, the method ReadLogFile returns a correct SelectListItem . I call this method from my controller action method. My entity contains a property called RunDatesDisplay which is an IEnumerable List. I could have created this property as a select list item but I do not want to reference the System.Web.Mvc namespace in my domain project?

The problem is I am unable to cast the selectlist item to an IEnumerable list in my entity to pass to the view. I have created a listview model and within the view I will call the editor template to render the checkboxes.

I just need help to correctly pass the selectlist item to the view. Should I pass the SelectListItem to the model property using ViewBag , for instance ViewBag.RunDatesDisplay = items(selectlistitem) or I should bind my selectlistitem to selectlist first?

Entity:

public class RunLogEntry
{

    public int ID { get; set; }

    public int RunID { get; set; }


    [NotMapped]
    public bool? LoadFileAttached { get; set; }

    [NotMapped]
    public bool? OutFileAttached { get; set; }

    [NotMapped]
    public string AttachedLoadListFileName { get; set; }

    [NotMapped]
    public string AttachedOutputFileName { get; set; }

    [NotMapped]
    public List<RunLogEntryTestExceptionDisplay> TestExceptionDisplay { get; set; }

    [NotMapped]
    public IEnumerable<RunLogEntryDatesDisplay> RunDatesDisplay { get; set; }
}

Method which does some processing and return a selectlistitem:

public static List<SelectListItem> ReadLogFile(List<string> fileNames)
{
    //Get collection of files and send to parser file by file:
    LogFile lf = new LogFile();


    var items = new List<SelectListItem>();
    foreach (var minDate in minDates)
    {
       var item = new SelectListItem() { Value = minDate.ToString(), Text = String.Format("{0} - {1}", minDate, minDate.AddMinutes(30)) };
        items.Add(item);
    }

    return items;
}

Controller Action(I did not include the entire code for the action)

//3. Send log file name collection to parser
if (logFiles != null && logFiles.Count > 0)
{
    var items = new List<SelectListItem>();

    items = FileImport.ReadLogFile(logFiles);
    **RunLogEntry.RunDatesDisplay = FileImport.ReadLogFile(logFiles);**

ViewModel:

public class RunLogRunDatesViewModel
{
    public IEnumerable<SelectListItem> RunLogRunDates { get; set; }
}

Editor Template

@model RunLog.Domain.Entities.RunDatesDisplay 

<tr>
    <td>
        @Html.DisplayFor(x => x.RunDate)
    </td>
</tr>

And finally my view:

<div id="runDatestreeview" title="Dialog Title" style="font-size: 10px; font-weight: normal;
            overflow: scroll; width: 800px; height: 450px; display: none;">
    <table class="grid" style="width: 600px; margin: 3px 3px 3px 3px;">
        <thead>
            <tr>
                <th>
                    Run Dates:
                </th>
            </tr>
        </thead>
        <tbody>
            @if (Model.RunDatesDisplay != null)
            {
                @Html.EditorFor(x => x.RunDatesDisplay)
            }
        </tbody>
    </table>
</div>

Answer 1

You can create custom type with two properties, or just use Tuple class, so your ReadLogFile could be something like this

public static List<Tuple<string,string>> ReadLogFile(List<string> fileNames)
{
   ...
   var items = new List<Tuple<string,string>>();
   foreach (var minDate in minDates)
   {
      var item = new Tuple<string, string>(minDate.ToString(), String.Format("{0} - {1}", minDate, minDate.AddMinutes(30));
      items.Add(item);
   }

   return items;
}

Your model:

public class RunLogRunDatesViewModel
{
       public SelectList RunLogRunDates { get; set; }
}

And your controller:

var model = new RunLogRunDatesViewModel();
List<Tuple<string,string>> items = FileImport.ReadLogFile(logFiles);
model.RunLogRunDates = new SelectList(items, "Item1", "Item2");

SelectList will try to get Value from "Item1" and Text from "Item2"

Or, as I said at start you can create simple class with two properties to avoid using of Tuple

UPDATE1 In .Net 2.0-3.5, you can create simple wrapper for it:

public class Tuple<T1,T2>
{
    public T1 Item1 {get;set;}
    public T2 Item2 {get;set;}
}