Find item from Dropdown, when dropdown binds with Objects like List, Dictionary etc.

Find item from Dropdown, when dropdown binds with Objects like List<T>, Dictionary etc.

When your dropdown bind with List<Object> then you cannot find value from the dropdown list in simple way like we used to do in classic asp.net application

cboLanguage.SelectedIndex = cboLanguage.Items.IndexOf("10");

See in details below

Let's say you have one object called "Language"

public class Languages

{

    public string Code { get; set; }

    public string Name { get; set; }

}

And you are binding your Dropdown from this object List<Languages> like

  List<Languages> lngs = new List<Languages>();

  Languages lng = new Languages();

  lng.Code = "10";

  lng.Name = "Ritesh";

  lngs.Add(lng);

----

---- etc.

Binding dropdown with this List of Objects

cboLanguage.ItemSource = Lngs;

Now if you want to find value on the dropdown and set the index then it will be different approach NOT simple like

Wrong:   cboLanguage.SelectedIndex = cboLanguage.Items.IndexOf("10");

You have to select the complete object from the List<Languages> and then set the selected index for the dropdown

Right:

var item = lngs.Where(ip => ip.Code == "10").FirstOrDefault();

if (item != null)

{

   cboLanguage.SelectedIndex = cboLanguage.Items.IndexOf(item);

}     

In this way you can set default value for dropdown box.