Merge XLTM to PPTX Online for Free. Free Online XLTM to PPTX Merger. Merge XLTM 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"...