I need to programmatically access the current Autodesk.Revit.DB.Document and ActiveUIDocument from the opened project within my WinForms application

[Lee27]

I've developed an IExternalCommand add-in for Revit. Now, I've created a new WinForms project with a button that automatically opens a Revit project file using
System.Diagnostics.Process.Start("C:/tmp/wall.rvt");.
I need to programmatically access the current Autodesk.Revit.DB.Document and ActiveUIDocument from the opened project within my WinForms application. Essentially, I want to trigger the add-in's functionality directly from my WinForms app, just as it would be when manually invoked from the Revit ribbon. Is there a way to achieve this?

[jeremy_tammik]

Me too.

[Lee27]

Haha, apologies, I posted the wrong thing @jeremy_tammik ,
Here's my actual question:
I've developed an IExternalCommand add-in for Revit. Now, I've created a new WinForms project with a button that automatically opens a Revit project file using
System.Diagnostics.Process.Start("C:/tmp/wall.rvt");.
I need to programmatically access the current Autodesk.Revit.DB.Document and ActiveUIDocument from the opened project within my WinForms application. Essentially, I want to trigger the add-in's functionality directly from my WinForms app, just as it would be when manually invoked from the Revit ribbon. Is there a way to achieve this?

[jeremy_tammik · Accepted solution]

Yes. I answered your identical question in your duplicate thread:

• https://forums.autodesk.com/t5/revit-api-forum/i-need-to-programmatically-access-the-current-autodes...