/// <summary>
        /// cashierAndEventButton will store the user input into the global utilities file for future use,
        /// then create an excel file for this cashier or open/update an existing file,
        /// then will be redirected back to SaleDetails form
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void CashierAndEventButton_Click(object sender, EventArgs e)
        {
            // Creates the filepath for the cashier+event excel file
            string filePath = (GlobalUtilities.getMasterFilePath()).Remove((GlobalUtilities.getMasterFilePath()).LastIndexOf('\\') + 1);

            string[] dateTimeArray = (DateTime.Now.Date.ToString("dd/MM/yyyy")).Split('/');
            GlobalUtilities.setCashierAndEventFilePath(filePath + cashierNameTextBox.Text + "_" + eventNameTextBox.Text + "_" + dateTimeArray[0] + "-" + dateTimeArray[1] + "-" + dateTimeArray[2] + ".xlsx");

            // Checks if the file already exists, if so update, if not create a new file
            if (!System.IO.File.Exists(GlobalUtilities.getCashierAndEventFilePath())) // Create a new file
            {
                Excel.Application xlApp       = new Excel.Application();
                Excel.Workbook    xlWorkbook  = xlApp.Workbooks.Add(System.Reflection.Missing.Value);
                Excel.Worksheet   xlWorksheet = (Excel.Worksheet)xlWorkbook.Worksheets.get_Item(1);

                xlWorksheet.Cells[1, 1]  = "Customer Name";
                xlWorksheet.Cells[1, 2]  = "Barcode Number";
                xlWorksheet.Cells[1, 3]  = "Product Description";
                xlWorksheet.Cells[1, 4]  = "Price";
                xlWorksheet.Cells[1, 5]  = "Quantity";
                xlWorksheet.Cells[1, 6]  = "Total Amount";
                xlWorksheet.Cells[1, 7]  = "Customer Type";
                xlWorksheet.Cells[1, 8]  = "Cash";
                xlWorksheet.Cells[1, 9]  = "Debit";
                xlWorksheet.Cells[1, 10] = "Credit";
                xlWorksheet.Cells[1, 11] = "Check";
                xlWorksheet.Cells[1, 12] = "Salary Deduction";
                xlWorksheet.Cells[1, 13] = "Date";
                xlWorksheet.Cells[1, 14] = "Time";

                xlWorkbook.SaveAs(GlobalUtilities.getCashierAndEventFilePath());
                xlWorkbook.Close(true);
                xlApp.Quit();

                Marshal.ReleaseComObject(xlWorksheet);
                Marshal.ReleaseComObject(xlWorkbook);
                Marshal.ReleaseComObject(xlApp);
            }
            else
            {
                // Do nothing
            }

            this.Close();
            GlobalUtilities.setCashierName(cashierNameTextBox.Text);
            GlobalUtilities.setEventName(eventNameTextBox.Text);
        }