private void rpt_typ_cmb_SelectedIndexChanged(object sender, EventArgs e)
 {
     if (rpt_typ_cmb.SelectedIndex == 4 || rpt_typ_cmb.SelectedIndex == 5)
     {
         from_calander.Enabled            = false;
         to_calander.Enabled              = false;
         sort_supp_client_checkbx.Checked = false;
         sort_supp_client_checkbx.Enabled = false;
         summarize_checkbox.Checked       = false;
         summarize_checkbox.Enabled       = false;
     }
     else
     {
         from_calander.Enabled = true;
         to_calander.Enabled   = true;
     }
     if (rpt_typ_cmb.SelectedIndex == 1)
     {
         supplierClientcmb.Enabled        = true;
         sort_supp_client_checkbx.Enabled = true;
         summarize_checkbox.Enabled       = true;
         sort_supp_client_checkbx.Checked = true;
         string selectStatement = "SELECT client_id as 'Client Id', name as 'Client Name' FROM client";
         DatabaseHandler.populateDispatchCombobox(selectStatement, supplierClientcmb);
     }
     else if (rpt_typ_cmb.SelectedIndex == 3)
     {
         supplierClientcmb.Enabled        = true;
         sort_supp_client_checkbx.Enabled = true;
         sort_supp_client_checkbx.Checked = true;
         summarize_checkbox.Enabled       = true;
         string selectStatement = "SELECT supplier_id as 'Supplier Code', name as 'Supplier' FROM SUPPLIER";
         DatabaseHandler.populateCombobox(selectStatement, supplierClientcmb);
     }
     else if (rpt_typ_cmb.SelectedIndex == 2)
     {
         supplierClientcmb.DataSource = null;
         supplierClientcmb.Items.Clear();
         supplierClientcmb.Enabled        = false;
         sort_supp_client_checkbx.Checked = false;
         sort_supp_client_checkbx.Enabled = false;
         summarize_checkbox.Enabled       = true;
     }
     else if (rpt_typ_cmb.SelectedIndex == 0)
     {
         supplierClientcmb.DataSource = null;
         supplierClientcmb.Items.Clear();
         supplierClientcmb.Enabled        = false;
         sort_supp_client_checkbx.Checked = false;
         sort_supp_client_checkbx.Enabled = false;
         summarize_checkbox.Enabled       = true;
     }
 }
        private void populateDispatchCombo()
        {
            string selectStatement = "SELECT client_id as 'Client Id', name as 'Client Name' FROM client";

            DatabaseHandler.populateDispatchCombobox(selectStatement, clientComboBox);
        }