Question

What’s the best tool to import an excel spreadsheet in C# these days? I’m currently using Interop.Excel.dll.

Answer 1

You can use the Jet OLEDB Provider:

connection.Open "Provider=Microsoft.Jet.OLEDB.4.0;" & _
           "Data Source=c:\somepath\mySpreadsheet.xls;" & _
           "Extended Properties=""Excel 8.0;HDR=Yes""" 

Where "HDR=Yes" means that there is a header row in the cell range
(or named range), so the provider will not include the first row of the
selection into the recordset.

Ref: how to use ADO to read and write data in Excel workbooks

See also:

• C# – ASP.NET – Import and Export Excel – What is the best library?
• Reading Excel files from C#