Hello,

Do you want to export data in one table or different tables to multiple sheets?

If the later one, you can create a template file, which the first sheet...

Hi,

This article(http://www.c-sharpcorner.com/UploadFile/d2dcfc/C-Sharp-create-excel-report-chart-contained-with-mark-designe/[/url]) shows a simple way to export data to template file(Excel). You can try to use mehtod in it.

Hope helpful!