@Marc, "behavior is not as expected" i totally agree with you and also believe your side doesn't work, but i was trying "still trying" to reproduce the error then i can provide the votes for this topic... even understand if i could miss some step...
I included the field "ExampleAL" to Content Type "Item" and change field to have multiple options and access to sub site "/Example" and create custom List "ExampleList" and have the following output with multiple values without issues.
- <d:ExampleALId m:type="Collection(Edm.Int32)">
What version of SharePoint this issue happen? Online, 2013, 2016? I had issues with SP on-premise REST call's and Online worked fine because of the version.
Did you use any Imported List for the connection or after some migration of content that could broke the content type id from top to bottom, just saying....
Strange, i was not able to reproduce this error using Office 365.
I create site Lookup column call "ExampleAL" with "Title" output to List in Root site, add to content type "Document" and "Update all content types inheriting from this type"
Go to sub site /Example and access to Document Library with new Field, update the field "ExampleAL" with data from other List "root web".
Make the REST Query "/Example/_api/web/Lists/GetByTitle('Documents')/items" and have the output <d:ExampleALId m:type="Edm.Int32">48</d:ExampleALId>
The only thing i dont like from this the fact i cannot expand the Field "ExampleAL" with other output field, because there isn't any reference to the List or the output expected in this case "Title" only ID... if the lookup object "ExampleAL" could be expanded that would be great.
This example from PnP could resolve this issue https://github.com/OfficeDev/PnP/tree/master/Samples/Core.ManageUserCustomAction
408 votesAndré Lage supported this idea ·