All DocumentSet derived ContentTypes' EventHandlers fires when uploading document

Question

I have made a custom "base" content type based on the Document Set content type. On this content type I attach 6 EventHandlers:
<ContentType ID="0x0120D5200088cd8a49c45a45dbb0b808d0934cd901"
Name="My Magical Base Document Set"
Description="My Base Document Set"
Group="Magical Content Types"
ProgId="SharePoint.DocumentSet"
PushDownChangedResourceFilesOnly="TRUE"
Version="0">
<FieldRefs />
<Folder TargetName="_cts/MyDocSetCustom" />
<XmlDocuments>
<XmlDocument NamespaceURI="http://schemas.microsoft.com/sharepoint/events">
<Receivers xmlns:spe="http://schemas.microsoft.com/sharepoint/events">
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemAdding</Name>
<Type>1</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemUpdating</Name>
<Type>2</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemDeleting</Name>
<Type>3</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemAdded</Name>
<Type>10001</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemUpdated</Name>
<Type>10002</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
<Receiver>
<Name>MagicalBaseDocumentEventHandlerItemDeleted</Name>
<Type>10003</Type>
<Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
<Class>MyMagicalProject.EventHandlers.MagicalBaseDocumentEventHandler</Class>
<SequenceNumber>50</SequenceNumber>
</Receiver>
</Receivers>
</XmlDocument>
</XmlDocuments>
</ContentType>
I then create 24 new content types based off of the above content type and I bind them to a document library.
After deployment, when the content types are all created and the library is created and have all the content types binded, I create a new document set in this library. I then try to add a new item (document).
This is where the interesting thing happens. When I add a Word or Excel document none of the EventHandlers are fired. But when I add a PDF, TXT, or XML document then the ItemAdding EventHandler is fired, 24 times - meaning the ItemAdding EventHandler is
fired for each DocumentSet content type binded to the list, before finally giving the uploaded document the content type "Document".
The document library gets created by a ListInstance on deployment, and all the content types are being binded in this ListInstance.
Is this a bug? Or have I done something wrong?

Answer 1

Hi,
I am trying to involve someone familiar with this topic to further look at this issue. There might be some time delay. Appreciate your patience.
Thanks 
Patrick Liang
Forum Support
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