jQuery multiselect在POST之后返回一个选择

Question

I have a Jquery multiselect control

$(function () {
    $(".multiselect").multiselect().multiselectfilter({
        filter: function (event, matches) {
            if (matches.length != null && !matches.length) {
                // do something
            }
        }
    });
});

And this is linked to a DropDownListFor

@Html.DropDownListFor(x => x.ID, new MultiSelectList(Model.Employees, "Id", "Name"), "Please Select", new {multiple = "multiple", @class = "multiselect"})  

When I press a button to post, the strongly typed model does send whoever has been selected in the list. Good. However, after the post, it only displays the first selected item in the DropDownListFor and not the others. I do send the model back when the post has happened with the IDs that are selected

// Model.ID which is a `int[]` is bounded to the `DropDownListFor` above has multiple values inside it. 
return View("View" Model)

Do I need to do something to the Jquery or the razor side to display the other selected items on postback?

Thanks

Answer 1

In msdn present a constructor which receives selectedValues.

public MultiSelectList(
    IEnumerable items,
    string dataValueField,
    string dataTextField,
    IEnumerable selectedValues
)

@Html.DropDownListFor(x => x.ID, new MultiSelectList(Model.Employees, "Id", "Name", Model.ToList()), "Please Select", new {multiple = "multiple", @class = "multiselect"}) 

Answer 2

Wow, OK, I found the problem.

I am not sure if its a .NET bug or something I need to change in my code, but changing

@Html.DropDownListFor(x => x.ID, new MultiSelectList(Model.Employees, "Id", "Name"), "Please Select", new {multiple = "multiple", @class = "multiselect"}) 

To

@Html.ListBoxFor(x => x.ID, new MultiSelectList(Model.Employees, "Id", "Name"), "Please Select", new {multiple = "multiple", @class = "multiselect"}) 

Just magically works.

Now, In my searching for a solution, I never saw one post to say "DropDownListFor's do not work with multiSelectList or anything on them lines but I wou;ld be happy for someone to explain if its something I done wrong?

However, this may save someone searching for hours for the solution.

Thanks to everyone who helped :)