I have updated the AttachObjectGraph code lately. It has been fixed to handle correctly - I hope - inheritance and recursivity in the entity model. I have also fixed an issue related to VB.NET compatibility (apparently, a Lambda expression is compiled differently from VB.NET as from C#).

Not only the code of the AttachObjectGraph method was fixed, I've also extended the sample to contain test methods of the different situations. Therefore, the model has been extended with a recursive element (nestable CatalogFolders), and inheritance (Customer and Supplier as subtype of Contact):

Unfortunately, my account on CodeProject has been corrupted and my requests to fix this have remained unanswered. Therefore, the download and article content on CodeProject will not be updated. I really hope CodeProject will restore my account such that I can continue to provide updates there too.

AttachObjectGraph code + sample (v3)
CodeProjectAttachObjectGraphSample3.zip (44.11 kb)