/// <summary>
/// Print the current workbook to the printer else to the default printer.
/// </summary>
/// <param name="printerToUse">the printer name to print the document to.</param>
protected void PrintWorkbook(string printerToUse = "")
{
_workbook.PrintOut(
_refMissing,
_refMissing,
_refMissing,
_refMissing,
_refMissing,
_refMissing,
_refMissing,
_refMissing);
}