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GemBox.Spreadsheet is a .NET component that provides elegant and high performance way to write and read from XLS files (BIFF format), CSV files (text format) or XLSX files (Excel 2007 XML format) without the need for Microsoft Excel on either the developer or client machines. Generated files can be opened in any Excel version from Office 97 and any application supporting the BIFF8 format (like OpenOffice). Fully generic HTML export (XHTML format) is also supported. GemBox.Spreadsheet Free comes free of charge while GemBox.Spreadsheet Professional is a commercial version (licensed per developer). Server deployment is royalty free.
 
For more info visit: http://www.GemBoxSoftware.com/GBSpreadsheet.htm
 
Most common uses of GemBox.Spreadsheet:
* CSV/XLS/XLSX files reading, writing or modification
* HTML export from CSV/XLS/XLSX files
* Filling of XLS/XLSX forms
* Conversion between CSV, XLS, XLSX and HTML files
* Splitting of XLS/XLSX files into multiple files (and other way)