Bytescout Spreadsheet SDK

Aimed at software developers and web designers, Bytescout Spreadsheet SDK is a component that facilitates a simple API enabling end users to read and write information from and to spreadsheets with the XLS (Office 97-2010), XLSX Office 2007-2010, ODS (OpenOffice Calc) and CSV format as well as to export files to PDF format.
Its not mandatory to have Microsoft Excel installed to be able to work with this library since it comes bundled with its own custom-made engine for opening, creating and calculating spreadsheets. According to Microsofts current policy, its not recommended to automate Office applications using unattended client programs or components that arent interactive, which also includes ASP.NET, ASP, NT Services, and DCOM.
Spreadsheets can be put together using managed .NET source code thats compatible with various security methods available for ASP.NET web servers. The utility supports mono .NET Framework too. It contains over 150 predefined code samples for ASP.NET, VB.NET, C#, ASP Classic, and Visual Basic 6. Moreover, Bytescout Spreadsheet SDK a has command-line mode along with .NET and ActiveX interfaces.
When it comes to formula calculations, add-in formulas like XIRR and standard functions are supported. It features cells, rows, columns and worksheets, together with Unicode support. Several tutorials are available at the developers website.System requirements.NET Framework 2.0 or higher
Limitations in the unregistered versionReminder messages added to XLS