The ComboBox.FindString method returns an integer. The Items.IndexOf method
takes an object as a parameter and finds that object in the list. Since the
object in question is an integer, it doesn't find it. Instead, you should
use:

combobox1.SelectedIndex = combobox1.FindString(myString)

Hi Robin

I have the same issue and here is the question again with a complete
code sample

I have the code below to fill a combobox.  I would appreciate any
comments on a better way to do this fill.

My main problem is how do I set the selected combo box display value
based on the "Id" column  if the Id is  "paytype" .  Also once the user
selects a combobox item from the dropdown how do I then retrieve the
"paytype" from the Id column.

        void Fill_LookupType()
        {
            int nItem;
            nItem = 0;

            string select = "SELECT description, lookuptypevalue ";
            select += "FROM lookuptypes ";
            select += "WHERE active = 1 ";
            select += "ORDER BY description ASC ";
            dbConnect Connection = new dbConnect();
            OdbcConnection conn = new  OdbcConnection(
@Connection.Connect());
            conn.Open();
            OdbcCommand cmd = new OdbcCommand(select,conn);
            OdbcDataReader aReader = cmd.ExecuteReader();

            DataTable list = new DataTable();
            list.Columns.Add(new DataColumn("Display", typeof(string)));
            list.Columns.Add(new DataColumn("Id", typeof(string)));

            while(aReader.Read())
            {
                list.Rows.Add(list.NewRow());
                list.Rows[nItem][0] = aReader.GetString(0);
                list.Rows[nItem++][1] = aReader.GetString(1);
            }

            aReader.Close();
            conn.Close();

            this.cb_LookupType.DataSource = list;
            this.cb_LookupType.DisplayMember = "Display";
            this.cb_LookupType.ValueMember = "Id";
            ;

           }