private void btn_delete_Click(object sender, EventArgs e)
        {
            //Client has invoice ?
            bool hasinvoice = sql.ClientHasInvoiceCheck(FM_LoginScreen.conString, "InvoiceTable", cb_clientselection.Text);

            if (hasinvoice == true)
            {
                MessageBox.Show("Unable to delete client!\n" + tb_clientName.Text + " has invoices present", "SQL Conflict");
                return;
            }

            //delete a row in client database
            if (tickBox_editMode.Checked)
            {
                string            message = "You are about to delete Client: " + tb_clientName.Text;
                string            caption = "ClientTable";
                MessageBoxButtons buttons = MessageBoxButtons.YesNo;
                DialogResult      result  = MessageBox.Show(message, caption, buttons);
                if (result == DialogResult.Yes)
                {
                    sql.RemoveRow(FM_LoginScreen.conString, "ClientTable", "ClientID", cb_clientselection.Text);

                    tickBox_editMode.Checked = false;
                }
            }
        }
        private void btn_delete_Click(object sender, EventArgs e)
        {
            if (tickBox_editMode.Checked)
            {
                string            message = "You are about to Delete Invoice: " + lb_invoiceID.Text + "\nThat belongs to: " + lb_clientID.Text;
                string            caption = "InvoiceTabel";
                MessageBoxButtons buttons = MessageBoxButtons.YesNo;
                DialogResult      result  = MessageBox.Show(message, caption, buttons);
                if (result == DialogResult.Yes)
                {
                    sql.RemoveRow(FM_LoginScreen.conString, "InvoiceTable", "InvoiceID", lb_invoiceID.Text);

                    tickBox_editMode.Checked = false;
                    Set_Data_Table();
                }
            }
        }