如何将哈希数组转换为散列值数组?

I have an array of hashes:

我有一组散列:

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}]

How can I convert it to array of values:

如何将其转换为值数组:

["male", "male", "female"]

6 个解决方案

#1

A generic approach to this that would take into account other possible keys:

为此采取的一种一般性办法是考虑到其他可能的要点:

list = [{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}]

# Collect the 'sex' key of each hash item in the list.
sexes = list.collect { |e| e['sex'] }

#2

In this case,

在这种情况下,

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}].map(&:values).flatten

should work.

应该工作。

It takes an array from each hash, then flatten the nested array.

它从每个散列中获取一个数组，然后将嵌套数组变平。

#3

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}].flat_map(&:values)

#4

arr = [{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}]
arr.map(&:values).flatten

EDIT: As directed by @tadman. Thanks!

编辑:由@tadman指导。谢谢!

#5

You can "map" the elements inside array, take the values of hashes, them "flatten" the resultant array.

您可以“映射”数组中的元素，取散列的值，它们“平坦化”结果数组。

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}].map{|h| h.values }
=> [["male"], ["male"], ["female"]]

[["male"], ["male"], ["female"]].flatten
=> ["male", "male", "female"]

In a single line, you can:

在一行中，你可以:

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}].map{|h| h.values }.flatten

or:

或者:

[{"sex"=>"male"}, {"sex"=>"male"}, {"sex"=>"female"}].map(&:values).flatten

Docs:

文档:

http://www.ruby-doc.org/core-1.9.3/Hash.html#method-i-values
http://www.ruby-doc.org/core-1.9.3/Hash.html method-i-values
http://ruby-doc.org/core-1.9.3/Array.html#method-i-flatten
http://ruby-doc.org/core-1.9.3/Array.html method-i-flatten
http://ruby-doc.org/core-1.9.3/Array.html#method-i-map
http://ruby-doc.org/core-1.9.3/Array.html method-i-map

#6

-2

    arr = Array.new 
    my_hash.each do |el|
      #collect them here...
      arr.push(el["sex"]);
    end

Hope it helps

希望它能帮助

#1