private void cboVenueNames_SelectedIndexChanged(object sender, EventArgs e) { cboYear.SelectedIndex = -1; cboMonth.SelectedIndex = -1; cboYear.Items.Clear(); pnlAnalysis.Visible = false; pnlMonth.Visible = false; pnlYear.Visible = false; btnAnalyseVenue.Visible = false; btnReset.Visible = false; if (cboVenueNames.SelectedIndex >= 0) { Venue ven = new Venue(); ven.setName(cboVenueNames.Text); ven.setVenueDetails(); List <String> years = ven.getYears(); if (years.Count > 0) { cboYear.Items.AddRange(years.ToArray()); pnlYear.Visible = true; } else { MessageBox.Show("There is no analysis available for " + cboVenueNames.Text, "Analysis Unavailable", MessageBoxButtons.OK, MessageBoxIcon.Error); cboVenueNames.SelectedIndex = -1; } } }