Merge SPREADSHEETML to XLSM Online for Free. Free Online SPREADSHEETML to XLSM Merger. Merge SPREADSHEETML to Word, Excel, PPTX, PDF, JPG, HTML, ODS, SVG, XPS and more.... Upload your files, call Workbook.Combine method for merging...aspose.cells.Workbook; Workbook workbook = new Workbook( "Input.xlsx"...