This article will help you how to export SQL data to excel. For this we will be using Microsoft.Interop.Office.Excel namespace and C#. The classes and interfaces in Microsoft.Interop.Office.Excel gives support for interoperability
This article helps you to read data from Microsoft Excel sheets. We can use OleDb data provider to get connected C# code to excel. It will give you step by step implementation for importing data from already created xls/xlsx file.