需要帮助理解这段代码,据我所知,我知道“<<”附加到集合但在这里它正确保存记录,如果不调用.save方法怎么办？
#user.rb
has_many :saved_properties,through: :property_saves,source: :property
#users_controller.rb
def update
if @user.saved_properties << Property.find(params[:saved_property_id])
render plain: "Property saved"
end
解决方法
也许查看源代码会对你有所帮助.这是我基于<<<<<<< activerecord中的方法：
def <<(*records) proxy_association.concat(records) && self end
rails/collection_proxy.rb at 5053d5251fb8c03e666f1f8b765464ec33e3066e · rails/rails · GitHub
def concat(*records)
records = records.flatten
if owner.new_record?
load_target
concat_records(records)
else
transaction { concat_records(records) }
end
end
rails/collection_association.rb at 5053d5251fb8c03e666f1f8b765464ec33e3066e · rails/rails · GitHub
def concat_records(records,should_raise = false)
result = true
records.each do |record|
raise_on_type_mismatch!(record)
add_to_target(record) do |rec|
result &&= insert_record(rec,true,should_raise) unless owner.new_record?
end
end
result && records
end
rails/collection_association.rb at 5053d5251fb8c03e666f1f8b765464ec33e3066e · rails/rails · GitHub
def insert_record(record,validate = true,raise = false)
set_owner_attributes(record)
set_inverse_instance(record)
if raise
record.save!(validate: validate)
else
record.save(validate: validate)
end
end
def insert_record(record,raise = false)
ensure_not_nested
if record.new_record? || record.has_changes_to_save?
if raise
record.save!(validate: validate)
else
return unless record.save(validate: validate)
end
end
save_through_record(record)
record
end
免责声明：我不熟悉Rails源代码,但你有一个有趣的问题.