哈希删除除特定键之外的所有内容 [英] Hash remove all except specific keys

问题描述

我想从散列中删除除给定键之外的所有键.

I would like to remove every key from a hash except a given key.

例如:

{
 "firstName": "John",
 "lastName": "Smith",
 "age": 25,
 "address":
 {
     "streetAddress": "21 2nd Street",
     "city": "New York",
     "state": "NY",
     "postalCode": "10021"
 },
 "phoneNumber":
 [
     {
       "type": "home",
       "number": "212 555-1234"
     },
     {
       "type": "fax",
       "number": "646 555-4567"
     }
 ]
}

我想删除除firstName"和/或address"之外的所有内容

I want to remove everything except "firstName" and/or "address"

谢谢

推荐答案

其他一些选项:

h.select {|k,v| ["age", "address"].include?(k) }

或者你可以这样做:

class Hash
  def select_keys(*args)
    select {|k,v| args.include?(k) }
  end
end

所以你现在可以说:

h.select_keys("age", "address")

这篇关于哈希删除除特定键之外的所有内容的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！