private void saveAsTxtBtn_Click(object sender, EventArgs e)
 {
     if (string.IsNullOrEmpty(this.fileNameTbx.Text))
     {
         createAndShowSaveFileDialogForExportingFileName();
     }
     if (!string.IsNullOrEmpty(this.fileNameTbx.Text))
     {
         StudentSignRecordExporter.toTxt(record, this.fileNameTbx.Text);
         MessageBox.Show(" 已匯出成TXT檔案!");
     }
 }
 private void saveAsExcelBtn_Click(object sender, EventArgs e)
 {
     if (string.IsNullOrEmpty(this.fileNameTbx.Text))
     {
         createAndShowSaveFileDialogForExportingFileName();
     }
     if (!string.IsNullOrEmpty(this.fileNameTbx.Text))
     {
         try
         {
             StudentSignRecordExporter.toExcel(record, this.fileNameTbx.Text);
             MessageBox.Show(" 已匯出成EXCEL檔案!");
         }
         catch (Exception err)
         {
             MessageBox.Show("匯出失敗!請確認電腦上已安裝Excel!");
         }
     }
 }