1. 数组的元素是Hash,请按照Hash给数组排序
- >> arr << {:name => 3, :type1 => 'b'}
- => [{:type1=>"a", :name=>1}, {:type1=>"c", :name=>2}, {:type1=>"b", :name=>3}]
- >> arr.sort_by{|x| x[:type1]}
- => [{:type1=>"a", :name=>1}, {:type1=>"b", :name=>3}, {:type1=>"c", :name=>2}]
- >> {|x, y| x[:type1] <=> y[:type1]}
- => [{:type1=>"a", :name=>1}, {:type1=>"b", :name=>3}, {:type1=>"c", :name=>2}]
2. 下面代码运行之后结果是什么
- class User < ActiveRecord::Base
- after_save :set_name
- private
- def set_name
- self.update_attribues(:name => 'Larry')
- end
- end
- (:name => "Woe")
结果是死循环,一直save after_save.怎么办呢
他说了个改
before_save
然后改
= "Larry"