Bytescout Spreadsheet SDK 

Read and write XLS, XLSX from ASP.NET, .NET, VB, C#, PHP and other programming languages without Excel installed! Supports formula calculations, text formatting, rows, columns, sheets management and much more! Can be used from legacy Visual Basic 6 and ASP classic, Delphi through special ActiveX wrapper with improved XLS and XLSX formats support and formula calculations

Technical details:

# 150+ source code samples ready to copy and paste from!

# Writing for XLS, HTML, TXT, CSV, XML support;

# Exports to PDF without any other libraries required;

# Reading for CSV, XLS (Office 97-2010), XLSX (Office 2007-2010) and ODS (Open Office Calc) support;

# Formula calculations (standard functions, add-in formula like XIRR) support;

# Can be used in Visual C#, Visual Basic.NET and ASP.NET;

# Cells, columns, rows, worksheets support;

# Unicode support;

# 12 chart types supported;

# Cell formatting (font, color, border style, alignment) is supported;

# Capable of changing existing Excel documents (change data and save modified document, add or remove rows, columns);

# Export XLS into CSV, TXT, HTML and XML, PDF;

# Reads Excel files into dataset;

# Convert spreadsheets from command line or .bat command files using Spreadsheet SDK Console version.