I’m currently looking at the Excel 2010 XLL SDK which is part of the Office 2010 Technical Preview. I’ve already built and tested my managed XLL system with Excel 2010 on x86 but I needed the new XLL SDK to be able to build for the x64 version of Excel. The SDK doesn’t ship as part of the main Office 2010 installation, you have to ask for it. So far things look reasonably good in x86 mode.
Once I got the simple managed Real Time Data servers working in Excel I decided it was time to add asynchronous worksheet functions. This is the last major feature on my todo list and once it’s complete I’ll be ready to start thinking about beta testing my Managed XLL product. The idea behind asynchronous worksheet functions is that some worksheet functions may take a long time to complete and it would be better to run them in the background rather than have them block Excel’s recalculations whilst they complete.
I’m currently working on adding easy to use Real Time Data server support to my Managed XLL Excel Addin system. This lets you use the =RTD() functionality of Excel to push real time data into your spreadsheets without needing to understand COM and without needing to register any COM objects on your machine. You simply add some attributes to your managed code, compile your assembly and drop it in the same directory as the Managed XLL and it does the rest.
Back in December and January I was working on the initial phases of a system to allow the development of custom Excel worksheet functions in managed code using the Excel XLL ‘C’ interface (Excel4v). Phase 1 finished with us having a pretty workable system that the client could go live with. The only problem was that we skipped the key ease of use part of the project due to time and budget constraints.
As I mentioned a while back, I’m writing a managed XLL style add-in system for Excel for one of my clients at the moment. This is going pretty well, most of the custom marshalling code is now done and we can write code in C# and expose it to Excel as worksheet functions. Over Christmas I picked up a copy of Excel Add-in Development in C/C++: Applications in Finance by Steve Dalton.
One of my current clients has got me drifting back towards my Investment Banking roots by developing an Excel addin for them. Luckily for me it’s a banking client with a twist compared to my previous banking clients; they’re happy for me to work as an external consultant, doing most of the work from my office at home and working on my contract terms. The development work so far has been quite interesting.