包括控制器中的模块

Question

我在 ruby​​ on rails 应用程序的 lib 目录中做了一个模块 就像

module Select  

  def self.included(base)
    base.extend ClassMethods
  end 

 module ClassMethods

    def select_for(object_name, options={})

       #does some operation
      self.send(:include, Selector::InstanceMethods)
    end
  end

我在像这样的控制器中调用了它

include Selector

  select_for :organization, :submenu => :general

但我想在函数中调用它 即

 def select
  #Call the module here 
 end

Answer 1

让我们澄清一下：您在模块中定义了一个方法，并且您希望在实例方法中使用该方法。

class MyController < ApplicationController
  include Select

  # You used to call this in the class scope, we're going to move it to
  # An instance scope.
  #
  # select_for :organization, :submenu => :general

  def show # Or any action
    # Now we're using this inside an instance method.
    #
    select_for :organization, :submenu => :general

  end

end

我将稍微更改您的模块。这使用include 而不是extend。 extend 用于添加类方法，include 用于添加实例方法：

module Select  

  def self.included(base)
    base.class_eval do
      include InstanceMethods
    end
  end 

  module InstanceMethods

    def select_for(object_name, options={})
       # Does some operation
      self.send(:include, Selector::InstanceMethods)
    end

  end

end

这会给你一个实例方法。如果你想要实例和类方法，你只需添加 ClassMethods 模块，并使用extend 而不是include：

module Select  

  def self.included(base)
    base.class_eval do
      include InstanceMethods
      extend  ClassMethods
    end
  end 

  module InstanceMethods

    def select_for(object_name, options={})
       # Does some operation
      self.send(:include, Selector::InstanceMethods)
    end

  end

  module ClassMethods

    def a_class_method
    end

  end

end

这样就清楚了吗？在您的示例中，您将模块定义为Select，但在控制器中包含Selector...我只是在代码中使用了Select。