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Following the Rails 2.0 hype, I’ve been playing around with it and decided to share a first impression: Scaffolding is gone!
But wait, before you knock your head against the wall, let me tell you something: I lied
Scaffolding is not really gone. It’s just changed a bit.
How can I tell? Well, as a good developer I thought: “I’ll just create a scaffold with the new version and see what’s different”
I fired up a terminal, created a news rails application and generated a new model:
$ script/generate model Contact name:string email:string - yes you can do this in rails 2.0, and these fields get into your model’s migration!
Now the I have a new model, it’s time for a controller to manage it:
$ script/generate controller Contacts
So your controller would look something like this huh?
class ContactsController < ApplicationController
scaffold :contact
end
Well, too bad! The method scaffold is gone from ActionController::Base! And I’m not lying this time!
Now that the dynamic scaffold is gone, we’re left with the static one.
Ok, let’s try it then:
$ script/generate scaffold contact
And it won’t work again! At the end of the output, you will get something like this:
Another migration is already named create_contacts: db/migrate/001_create_contacts.rb
It really means that if your model is meant to be used by a scaffold, you better generate it in the same line. It will fail, afaik, if the model previously existed. Destroy yout model and controller, and execute the following:
$ script/generate scaffold Contact name:string email:string
Done! Just run your migrations, startup your server and your new scaffold in rails 2.0 will be working gracefully!
It took me a while to discover this changes because I didn’t find it well documented. But maybe I was not looking in the right places.

现在Rails2.0的scaffold是这样的语法：
script/generate scaffold ModelName [field:type  field:type]

去掉了1.2前使用的语法：
script/generate scaffold ModelName [ControllerName] [action, ...]

现在就不能像以前那样建了model和controller后再用scaffold了。