ActiveRecord :: Relation对象如何调用类方法?
class Project < ActiveRecord::Base
has_many :tasks
end
class Task < ActiveRecord::Base
belongs_to :project
def self.initial_tasks # class methods
# here return initial tasks
end
end
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现在我们可以致电:
Project.first.tasks.initial_tasks # how it works
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initial_tasks 是一个类方法,我们不能在对象上调用类方法.
Project.first.tasks返回一个ActiveRecord :: Relation对象,那怎么能调用initial_tasks呢?
请解释.