Excel-Dna is an independent project to integrate .NET into Excel. The primary target is the Excel user who currently writes VBA code for functions and macros, and would like to start using .NET. Also interested would be C/C++ based .xll add-in developers who want to use the .NET framework to develop their add-ins.
The Excel-Dna Runtime is free for all use, and distributed under a permissive open-source license that also allows commercial use.
Excel-Dna is developed using .NET, and users have to install the freely available .NET Framework runtime. The integration is by an Excel Add-In (.xll) that exposes .NET code to Excel. The user code can be in text-based (.dna) script files (C#, Visual Basic or F#), or compiled .NET libraries (.dll). Excel-Dna supports both the .NET runtime version 2.0 (which is used by .NET versions 2.0, 3.0 and 3.5) and version 4. Add-ins can target either version of the runtime, and concurrent loading of both runtime versions into an Excel instance is supported.
Excel versions ’97 through 2010 can be targeted with a single add-in. Advanced Excel features are supported, including multi-threaded recalculation (Excel 2007 and later), registration-free RTD servers (Excel 2002 and later) and customized Ribbon interfaces (Excel 2007 and 2010). Most managed UDF assemblies developed for Excel Services can be exposed to the Excel client with no modification.
