This continues my previous checklist on getting started with Excel Services. Here, I’ll append a walkthrough for creating, deploying and updating User-Defined Function assemblies with Excel Services. 4. Create and deploy a UDF assembly 4.1 Create a UDF assembly in Visual Studio (SampleUdf.dll)...

I've been thinking more about calling unmanaged XLL UDFs from managed code than about managed automation add-ins lately, but an automation add-in issue came up the other day, and I thought I'd throw it out there. If you want to build managed UDFs without going to the extreme of managed XLLs, you have...

In my previous post , I looked at how to build a VSTO add-in that invokes native XLL UDFs via the Excel COM OM (specifically, Application.Run). In this second part, I'll look at the same managed client calling the same XLL UDFs via the Windows API instead of Excel's COM OM, specifically using LoadLibrary...

As part of a little ongoing investigation, I wanted to communicate between a managed add-in and a native XLL UDF. As I was writing this up, it turned out to be a much longer post that I planned, so I've split it into two parts (I'll post the second part in the next week or so, mince pies permitting)...

As part of a little investigation I'm doing at present, I needed to build some simple native XLLs for testing purposes. This was the first time I had a need to build XLLs since the Excel XLL SDK was updated back in September. The updated Excel 2007 XLL SDK is available for free download here . The online...

In my previous posts on shimming Excel automation add-in UDFs, I've used simple examples where the methods tended to take and return standard types such as doubles and ints. Someone asked a question recently - what about Excel types as parameters? In other words, how do you write the shim for a method...