Fighting to get a COM visible VSTO Addin so its method can be used by VBA

So I am having some troubles and am learning too much about old technology. In short – my interface is COM visible to my VBA in my Excel code, but not the class. Crap – add the word public in front of class – fixed it. None-the-less here is a blog of what helped me solve my issue. I WANT (insist) early binding (aka intellisense 🙂 ) (Something close to my issue). Want to know even more … look at the links at the bottom of this article.

First – set up things properly.

Have a GUID for the interface IMyInterface and on the class MyClassO
Have the dual interface turned on on the interface and class

have a class MyClassO that inherits these Interface StandardOleMarshalObject, IMyInterface

in the ThisAddin.cs … have the following method

private MyClassO utilities;
/// <summary>;
///
/// </summary>
/// <returns></returns>
protected override object RequestComAddInAutomationService()
{
if (utilities == null)
{
utilities = new MyClassO();
}return utilities;
}

Did you check the Object Broswer in VBA???
- Go to VBA Editor and press F2 or choose View-Object Browser
- Change the “All Libraries” pull down to the name of you namespace or library
- I saw my library – but just the interface.
Does the OLE / Com Object viewer show the same? It should
It did! so look at this article How COM works – this guy is WAY TO FAMILIAR – but is the reason I solved my issue – thanks man!

More articles that I wished I put here in my blog but was in my c# code so I copied it here – hope this helps