We have hundreds of process book displays (PDI files). All of them have got lot of custom VBA code inside. Is there anyway we can migrate the VBA code to .Net?
The simple answer is no; you have the same issue with VBA Macro's in Excel.
The long version. While it is possible to write .NET plugins to ProcessBook (PB) these aren't document specific; as far as I'm PB doesn't have the document model that is possible with VSTO (Visual Studio Tools for Office). I believe it would be difficult and cumbersome to replace all the VBA "scripts" with .NET plugins; just distributing them will be painful.
The story of VBA is a little frustrating. Microsoft's original plan was to replace VBA with VSTA (Visual Studio Tools for Applications). VSTA would run side-by-side with VBA, there would be no "automated" upgrade. VSTA is .NET based. Unfortunately VSTA appears to have died on the vine, the only Office app that supported it was InfoPath which has also died.
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