具有阵列标准的红宝石切片

Question

如何通过数组为 ruby​​ 中的散列创建一个切片，如下所示：

info         = { :key1 => "Lorem", :key2 => "something...", :key3 => "Ipsum" }
needed_keys  = [:key1, :key3]
info         = info.slice( needed_keys )

我想收到：

{ :key1 => "Lorem", :key3 => "Ipsum" }

Answer 1

的ActiveSupport的Hash#slice不带钥匙作为参数数组，你必须通过你想提取单参数，例如按键泼洒您的needed_keys数组：

info.slice(:key1, :key3)
# => {:key1=>"Lorem", :key3=>"Ipsum"}

info.slice(*needed_keys)
# => {:key1=>"Lorem", :key3=>"Ipsum"}