I need some help on how to restore the value of the lookup column of one of my sharepoint list.
Scenario:
I have 2 sharepoint lists.
LIST1
LIST2
LIST1 has a column A with type Extended Lookup Field, this references to column A of LIST2.
Recently, I added another field in LIST2. Then I performed, deactivate/activate | uninstall/install of LIST2.
NOW< the problem is the reference lookup of column A – LIST1 TO column A – LIST2 was lost.
Before when editing column A-LIST1, there is information written under:
Get information from:
column a – LIST2
Now, it's just blank…
Best Answer
The LookupList property contains the GUID of the original instance of LIST2. If LIST2 was deleted and a new instance was created, the new LIST2 will have a different GUID and your lookup field on LIST1 will not work.
And, unfortunately,
LookupList
cannot be changed directly:However, you can try the following:
Using reflection, you can try to call the internal SetFieldAttributeValue method and change the "List" attribute, which is what is used by the
LookupList
property.