public void NPOIFSReadCopyWritePOIFSRead() { FileStream testFile = POIDataSamples.GetSpreadSheetInstance().GetFile("Simple.xls"); NPOIFSFileSystem src = new NPOIFSFileSystem(testFile); byte[] wbDataExp = IOUtils.ToByteArray(src.CreateDocumentInputStream("Workbook")); NPOIFSFileSystem nfs = new NPOIFSFileSystem(); EntryUtils.CopyNodes(src.Root, nfs.Root); src.Close(); MemoryStream bos = new MemoryStream(); nfs.WriteFileSystem(bos); nfs.Close(); POIFSFileSystem pfs = new POIFSFileSystem(new MemoryStream(bos.ToArray())); byte[] wbDataAct = IOUtils.ToByteArray(pfs.CreateDocumentInputStream("Workbook")); Assert.That(wbDataExp, new EqualConstraint(wbDataAct)); }