Having found out how to do visual inheritance, I created some 20 classes that inherit from a base form in a new project.

I then tried to import all these, including the base form, into my existing project using "Project/Add existing items". All my inherited classes came in as if they were complete forms (1.e with a + in the solution explorer that reveals a designer and a resx) The project won't build because it says one or more of the controls (on the base form) are missing (presumably because it thinks they are complete forms in themselves). It actually says "The variable 'GroupBox1' is either undeclared or was never assigned."

So I then tried to add the other components from the original project to my new project, again with "Project/Add existing items". This time the forms in the original project have come across as three separate files - a vb, a resx and a designer.vb, and the forms have no visual components.

Any suggestions on how to merge these two projects successfully?

When you add the existing items, it seems to be copying the inherited forms into the current project's directory. Those forms are looking locally for the parent class and it's not there.

Instead make a class library and put the parent form there, along with any inherited forms that you want to use in other projects. Then in the second project, add a reference to the DLL. You should be able to create instances of the classes defined in the DLL and inherit from them.

Rod
RodStephens@vb-helper.com
Author of "Visual Basic 2005 Programmer's Reference"
http://www.vb-helper.com/vb_prog_ref.htm

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Thanks, Rod. I'll venture into the unknown waters of class libraries!

I'm now using code sharing instead (see my IDE topic)