Excel 2007 Addin - Technology options

We have a number of .xla/.xlam Excel Addins and the time has come to migrate to something easier to version control and maintain.

I'd like to write in C# if possible and the Addins will need to do the following sort开发者_开发技巧s of things:-

• Provide User Defined Functions to Excel
• Create and manipulate named ranges in the Excel sheet
• Pull data from external sources and populate cells in the Excel sheet

Currently all this is possible and simple to do with a .xlam what are the pros/cons of moving to VSTO or creating a C# Addin (I notice VS2010 has a New Project option of creating an Excel 2007 Addin).

Are there any good sources of documentation?

Thanks Dave

I would recommend you seriously look at Excel DNA (Free) or Addin Express (chargeable). Both provide .Net functions via the .XLL interface together with .COM to .NET interface if you need it.
Performance of both of these makes VSTO look like molasses, and installation is realtively simple.
For easy creation of performing UDFs XLDNA is VERY hard to beat.