Multiple DisplayMember using special class

Question

I am trying to get a ListBox to display a concatenation of multiple rows of table Accommodation.

Because I can't edit the datasource, I prepared a class, AccommodationEntity, which contains both the original Accommodation object and the string I want the ListBox to display.

However, for some reason, I fail to set the DisplayMember property of the ListBox, which thus displays the default jibber-jabber.

I set up the listbox as follows:

accommodationList.DisplayMember = "textToShow";
// load and set up accommodation
List<AccommodationEntity> relatedAccommodations = 
    dt.listHolidayAccommodation(relatedHoliday);
accommodationList.DataSource = relatedAccommodations;
accommodationList.Refresh();

The class for the objects stored in the datasource looks like this:

class AccommodationEntity
{
    public accommodation classicAccommodation;
    public string textToShow;

    public AccommodationEntity(stay relatedStay)
    {
        this.classicAccommodation = relatedStay.accommodation;

        string from = relatedStay.dateFrom.ToString();
        string to = relatedStay.dateTo.ToString();
        string city = relatedStay.accommodation.location.ToString();
        string hotelName = relatedStay.accommodation.name.ToString();

        this.textToShow = hotelName + ", " + city + " (" + from + " - " + to + ")";
    }
}

} `

And finally, there is a method which does some searching (returning correct objects):

public List<AccommodationEntity> listHolidayAccommodation(holiday selectedHoliday)
{
    List<AccommodationEntity> ubytovani = new List<AccommodationEntity>();

    var stays = from singleStay in selectedHoliday.stays
                select singleStay;

    foreach (stay singleStay in stays)
    {
        AccommodationEntity newStay = new AccommodationEntity(singleStay);
        ubytovani.Add(newStay);
    }

    return ubytovani;
}

I know the dataSource contains the right data, but for some reason, it seems the DisplayMember property remains set to "".

Any help would be appreciated.

Thanks.

Answer 1

Are you setting the DisplayMember and ValueMember properties? Have a look at the DataSource property on MSDN to see how they are setting all three properties.

UPDATE:

Try switching this:

accommodationList.DisplayMember = "textToShow";
// load and set up accommodation
List<AccommodationEntity> relatedAccommodations = 
    dt.listHolidayAccommodation(relatedHoliday);
accommodationList.DataSource = relatedAccommodations;

to this:

// load and set up accommodation
List<AccommodationEntity> relatedAccommodations = 
    dt.listHolidayAccommodation(relatedHoliday);
accommodationList.DataSource = relatedAccommodations;
accommodationList.DisplayMember = "textToShow";

Answer 2

Did you try to set the DisplayMember and DisplayValue like this. Where "Name"/"Value" is the name of the property in the Accomodation class.

List<AccommodationEntity> relatedAccommodations = dt.listHolidayAccommodation(relatedHoliday);
accommodationList.DataSource = relatedAccommodations;
accommodationList.DisplayMember = "Name";
accommodationList.ValueMember = "Value";

UPDATE:

Make sure textToShow is actually a Property, not just a public field.