rails:为模型创建脚手架以从超类继承吗? [英] rails: create scaffold for models to inherit from superclass?
问题描述
我是Rails的新手，仍然会弄湿我的脚，所以如果这是琐碎的事情或做事的错误方式"，请原谅我.
I'm new to Rails, still getting my feet wet, so please pardon me if this is either trivial or "the wrong way" to do things.
我想为某些脚手架模型创建一个超类.例如，我想为Men和Women创建一个支架，但是我希望它们都从People超类继承. Men和Women将从People类继承诸如height和weight之类的字段.
I'd like to create a superclass for some scaffolded models. For example, I'd like to create a scaffold for Men and for Women, but I want them both to inherit from a People superclass; Men and Women would inherit fields like height and weight from the People class.
在哪里/如何定义此People超类?如何通过脚手架定义子类Women?
Where/how do I define this People superclass? How do I define the subclasses Men and Women via scaffolding?
推荐答案
这是我考虑过要对应用程序进行处理的事情.我还没有做过，如果您是Rails的新手，我也不会推荐它.我要么完全制作单独的模型，要么制作一个模型，并使用属性gender(应为0或1)，然后创建一个返回对应性别字符串的方法.
This is something I've thought about doing with my application. I haven't done it yet, and I wouldn't recommend it if you are new to rails. I would either make separate models entirely, or make one model, and have the attribute gender, which should be either a 0 or a 1, and then make a method that returns the string for the corresponding gender.
编辑
所以我打开了rails控制台，从我看到的情况来看，完全有可能，您需要做的就是声明类，如果要使用其他表，则set_table_name
So I opened up the rails console, and from what I could see, it is possible totally possible, all you need to do is declare the class, and if you want to use different tables, set_table_name
class This < That
set_table_name :this
end
class There < This
set_table_name :there
end
或者您可以使用一张桌子，但是如果您尝试保持DRY，我将使用两张桌子.
Or you could use one table, but if your trying to stay DRY, I would use two.
如果要使用脚手架生成器，则必须为想要查看的每个类(男人和女人)运行典型的rails g scaffold Men.生成的模型继承自ActiveRecord::Base类.继承标记是小于符号(<).
If you want to use the scaffold generator, you will have to run the typical rails g scaffold Men for each class you want views for (men and women). The model that this generates inherits from the ActiveRecord::Base class. The inheritance marker is the less than symbol (<).
# THESE WILL BE THE DEFAULT GENERATED MODELS
class Men < ActiveRecord::Base
end
class Women < ActiveRecord::Base
end
然后您将手动创建超类User
You will then manually create the super class User
class User < ActiveRecord::Base
end
，然后编辑Men和Women模型以从User
and then edit the Men and Women models to inherit from User
# men.rb
class Men < User
end
# women.rb
class Women < User
end
让我们说您想用一个表子类化，您可以纠正该表的迁移，然后将attr_accessible添加到适当的子类中.
lets say you wanted to subclass with one table, you could would right the migrations for that table, and then add the attr_accessible to the appropriate subclass.
attr_accessible是rails安全功能.它确定可以在批量分配中设置哪些属性.与安全性，网站等级等相关的任何内容都不应访问.
attr_accessible is a rails security feature. It determines which attributes may be set in mass assignment. Anything related to security, site rank, etc. should not be accessible.
示例:
attr_accessible :favorite_food, :interests, :password, :email # THIS IS GOOD
attr_accessible :admin, :has_access_to_missile_launch_codes # THIS IS BAD
因为有人可能会通过
params => { :man => { :admin => true }}
主要要点是，使用这些attr_accessible将确定哪种类型的用户可以设置什么.显然，您可以通过将共享功能放在超类中来进行干燥.希望这会有所帮助
The main point is that using these attr_accessible will determine which type of user can set what. Obviously you can DRY this up by putting shared features in the super-class. Hope this helps
您还应该阅读有关super关键字和self关键字的信息.如果您运行的是继承的设置，则最终将要使用这些设置.
You should also read about the super keyword, and the self keyword. If your running an inherited setup you will eventually want to use these.
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