01.string connString = ConfigurationManager.ConnectionStrings["NorthwindConn"].ConnectionString;
02.conn = new SqlConnection(connString);
03.string query = "SELECT * FROM Customers";
04.SqlCommand cmd = new SqlCommand(query, conn);
05.conn.Open();
06.SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
07.DataTable dt = new DataTable();
08.dt.Load(dr);
09.
10.cboBookType.BeginUpdate();
11.cboBookType.DisplayMember = "BookTypeName";
12.cboBookType.ValueMember = "BookTypeID";
13.cboBookType.DataSource = dt;
14.cboBookType.EndUpdate();
