public static void SaveToFile(NPOI.SS.UserModel.IWorkbook workbook, string fileName)
{
System.IO.FileInfo fileInfo = new System.IO.FileInfo(fileName);
System.IO.FileStream fileStream = new System.IO.FileStream(fileInfo.FullName, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.ReadWrite);
workbook.Write(fileStream);
fileStream.Close();
workbook.Close();
}
