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Showing posts from June, 2012

Excel User Defined Functions with C# and ExcelDna

Adding user defined functions to Excel can be laborious, either you use VBA or COM. Why can't Microsoft make it easier to use Visual Studio and .NET within Excel? Enter ExcelDna . This example creates a static function in C# using Visual Studio. There is documentation that already describes this, what I am adding is: Use Visual Studio to create project Post Build Events to help create the final XLL file. NOTE: I hate Post Build Events. The ONLY exception is in this case where I am modifying the output of the final build. Post Build Events are Evil especially when used in a large development team. A better solutions is to create actual Build Scripts that do what I am about to do. You have been warned. First, create a new Class Library project. Use NuGet to add a reference to the Excel-DNA package. NuGet will also add ExcelDna.dna and ExcelDna.xll to your project. Rename them both to the name that you want your final output xll to be. In my case I renamed them to Scratch-ExcelDn