Question

给出一个类似的模型：

class SentenceItem < ActiveRecord::Base

  after_update :send_changes

  def send_changes
     #### Is it possible to do a diff here with dirty/changed? Showing what's changed since the last save?
  end

end

句子模型有一个文本字段。

是否可以在这里使用脏/更改进行差异？显示自上次保存以来发生了哪些变化？

由于

Answer 1

是的，有办法。来自ActiveModel::Dirty文档：

新实例化的对象不变：

person = Person.find_by_name('Uncle Bob')
person.changed?       # => false

更改名称：

person.name = 'Bob'
person.changed?       # => true
person.name_changed?  # => true
person.name_was       # => 'Uncle Bob'
person.name_change    # => ['Uncle Bob', 'Bob']
person.name = 'Bill'
person.name_change    # => ['Uncle Bob', 'Bill']

哪些属性已更改？

person.name = 'Bob'
person.changed        # => ['name']
person.changes        # => { 'name' => ['Bill', 'Bob'] }

Rails，在模型中是否有一种方法可以提供自上次更新以来的难度？

1 个答案: