arrays - 如何根据 Ruby 中另一个数组的值对散列进行排序？

Question

看起来小菜一碟，但是解决不了..

elements = ['one', 'two', 'three']

sort_me = {'three': 3, 'two': 2, 'one': 1}

sort_me.sort_by { |k, _| elements.index k }.to_h 没有按照应有的方式对其进行排序。哈希值保持不变。

所需的输出是 {:one=>1, :two=>2, :three=>3}。

Answer 1

您不需要对任何内容进行排序，也不需要创建查找表。您的数组已经按照您想要的方式排序，并且您的 sort_me 散列已经是一个查找表:

elements = ['one', 'two', 'three']
# => ["one", "two", "three"]
sort_me = {'three' => 3, 'two' => 2, 'one' => 1}
# => {"three"=>3, "two"=>2, "one"=>1}
elements.map{|key| [key, sort_me[key] ] }.to_h
# => {"one"=>1, "two"=>2, "three"=>3}

如果你想使用符号和字符串:

elements = ['one', 'two', 'three']
# => ["one", "two", "three"]
sort_me = {three: 3, two: 2, one: 1}
# => {:three=>3, :two=>2, :one=>1}
elements.map{|key| [key.to_sym, sort_me[key.to_sym] ] }.to_h
# => {:one=>1, :two=>2, :three=>3}

最后，如果散列中没有使用某些元素，您可以简单地删除具有nil 值的对:

elements = ['one', 'two', 'two_and_a_half', 'three']
# => ["one", "two", "two_and_a_half", "three"]
elements.map{|key| [key.to_sym, sort_me[key.to_sym] ] }.to_h
# => {:one=>1, :two=>2, :two_and_a_half=>nil, :three=>3}
elements.map{|key| [key.to_sym, sort_me[key.to_sym] ] }.reject{|k, v| v.nil? }.to_h
# => {:one=>1, :two=>2, :three=>3}