ruby-on-rails - 状态机转换轨道

Question

我有如下状态转换：

  [A,B] => C
  [B,C] => A

我正在使用 before_transition、after_transition 方法如下：

  before_transition :to => C do
  end

但是现在我遇到了使用上述方法的情况，如下所示

  before_transition :from=> A, :to => C do
  end

有没有办法做到这一点？

Answer 1

大概是这样

before_transition :A => :B, :do => :action
... ... ...
def action
    #do your stuffs here.
end

Answer 2

也许你可以使用

before_transition :to => 'canceled', :from => 'new_order', :do => [:cancel_account_movement]

def cancel_account_movement
   #blablabla
end