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