There is a thread out there that already discusses a little of it:
Integrate C++ program into VBA - QuantNetwork - Financial Engineering Forum
Are you asking because this is something you have to do? Also, do you want to use C# as a replacement for VBA macros, or do you want to call the Excel object model from a C# program? Those are totally different issues.
Joe, thanks. What I mean is integrated C# and Excel (not C++, it is C#).
Secondly, I want to know how call C# object model from Excel and vice versa.
I've had so much trouble with putting .NET on top of Excel, that I would not recommend it. For me it worked fine up to a point, but once I started doing a large amount of calculations/cell changes things would bog down and eventually would crash Excel. It got to be so much trouble that I gave up and ported it to be a stand alone VB .NET program. Things work great now, and it really didn't take that much more programming.
Have fun. Keep in mind that I tested it with VS2008 Team edition and Excel 2007.
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