Ruby:重命名哈希数组中的键？

Question

如何在 MongoDB 文档数组中将 _id 键重命名为 id？

所以，我想做这个:

[{"_id"=>"1", "name"=>"Matt"}, {"_id"=>"2", "name"=>"John"}, ...]

进入这个:

[{"id"=>"1", "name"=>"Matt"}, {"id"=>"2", "name"=>"John"}, ...]

Answer 1

ar = [{"_id"=>"1", "name"=>"Matt"}, {"_id"=>"2", "name"=>"John"}]
ar.each{|h| h.store('id',h.delete('_id'))}
ar # => [{"name"=>"Matt", "id"=>"1"}, {"name"=>"John", "id"=>"2"}]

如果你不想修改原始数组，请按以下方式操作:

ar = [{"_id"=>"1", "name"=>"Matt"}, {"_id"=>"2", "name"=>"John"}]
ar.map{|h| {"id"=>h['_id'], "name"=>h['name']} }
# => [{"id"=>"1", "name"=>"Matt"}, {"id"=>"2", "name"=>"John"}]