Do something like this:
class Annex < ActiveRecord::Base
has_and_belongs_to_many :documents
before_destroy { raise "Can't destroy Annex, because it's still associated to 1 or more documents" if documents.any? }
end
题
class Annex
has_and_belongs_to_many: :documents
end
class Document
has_and_belongs_to_many: :annexes
end
I want to implement this behavior: if the annex is associated to at least one document, it shouldn't be destroyed.
Is there a easy rails way of doing this or will I have to make a work around this?
Will I have to use a before_destroy method or something like that?
解决方案
Do something like this:
class Annex < ActiveRecord::Base
has_and_belongs_to_many :documents
before_destroy { raise "Can't destroy Annex, because it's still associated to 1 or more documents" if documents.any? }
end