What is the easiest and convenient way to export data (from gridview or datatable) to excel and download it

See more:

C#

ASP.NET

MS-Excel

Hi. I am developing a program that needs to export data (either from gridview or datatable whichever is good) to MS Excel.

Aside from these, do we have other option:
1. Use of ExcelInterop since it needs MS Office Excel to be installed in the server, or else it will prompt error
2. StreamWriter as this renders the gridview as HTML and prints the whole page instead of the control alone. It also does not support .xlsx file.
2. OpenXML

I've been trying to look for solution but doesnt seem to get one.
Thanks, Your suggestions will be highly appreciated!