Ruby数组转换的最佳方式

Question

实现以下目标的最好方法是什么?我在ABC下有以下一系列操作

ABC:-

ABC:Actions,
ABC:Actions:ADD-DATA,
ABC:Actions:TRANSFER-DATA,
ABC:Actions:EXPORT,
ABC:Actions:PRINT,
ABC:Detail,
ABC:Detail:OVERVIEW,
ABC:Detail:PRODUCT-DETAIL,
ABC:Detail:EVENT-LOG,
ABC:Detail:ORDERS 

我想将其格式化为：

ABC =>{Actions=> [ADD-DATA,TRANSFER-DATA,EXPORT,PRINT], Detail => [Overview, Product-detail, event-log,orders]}

Answer 1

可能有很多方法可以做到这一点，但这里只有一种：

a = ["ABC:Actions",
"ABC:Actions:ADD-DATA",
"ABC:Actions:TRANSFER-DATA",
"ABC:Actions:EXPORT",
"ABC:Actions:PRINT",
"ABC:Detail",
"ABC:Detail:OVERVIEW",
"ABC:Detail:PRODUCT-DETAIL",
"ABC:Detail:EVENT-LOG",
"ABC:Detail:ORDERS"]

a.map { |action| action.split(":") }.inject({}) do |m, s|
  m[s.at(0)] ||= {}
  m[s.at(0)][s.at(1)] ||= [] if s.at(1)
  m[s.at(0)][s.at(1)] << s.at(2) if s.at(2)
  m
end

map调用返回一个数组，其中原始数组中的每个字符串都被拆分为由:分隔的元素数组。例如[["ABC","Actions","ADD-DATA"] ... ]

然后，inject调用通过遍历这些“拆分”数组中的每一个来构建散列。它为第一个元素创建一个映射，如果不存在的话，映射到一个空的散列，例如"ABC" => {}。然后，它在散列中为第二个元素创建一个映射到一个空数组，例如"ABC" => { "Detail" => [] }。然后，它将第三个元素添加到该数组中，以获得类似"ABC" => { "Detail" => ["OVERVIEW"] }的内容。然后，它进入下一个“分割”数组，并以同样的方式将其添加到散列中。

Answer 2

我将这样做：

a = ["ABC:Actions",
"ABC:Actions:ADD-DATA",
"ABC:Actions:TRANSFER-DATA",
"ABC:Actions:EXPORT",
"ABC:Actions:PRINT",
"ABC:Detail",
"ABC:Detail:OVERVIEW",
"ABC:Detail:PRODUCT-DETAIL",
"ABC:Detail:EVENT-LOG",
"ABC:Detail:ORDERS"]

m = a.map{|i| i.split(":")[1..-1]}
# => [["Actions"],
#     ["Actions", "ADD-DATA"],
#     ["Actions", "TRANSFER-DATA"],
#     ["Actions", "EXPORT"],
#     ["Actions", "PRINT"],
#     ["Detail"],
#     ["Detail", "OVERVIEW"],
#     ["Detail", "PRODUCT-DETAIL"],
#     ["Detail", "EVENT-LOG"],
#     ["Detail", "ORDERS"]]

m.each_with_object(Hash.new([])){|(i,j),ob| ob[i] = ob[i] + [j] unless j.nil? }
# => {"Actions"=>["ADD-DATA", "TRANSFER-DATA", "EXPORT", "PRINT"],
#     "Detail"=>["OVERVIEW", "PRODUCT-DETAIL", "EVENT-LOG", "ORDERS"]}

Answer 3

用group_by做这件事很有趣:)

a = ['ABC:Actions',
'ABC:Actions:ADD-DATA',
'ABC:Actions:TRANSFER-DATA',
'ABC:Actions:EXPORT',
'ABC:Actions:PRINT',
'ABC:Detail',
'ABC:Detail:OVERVIEW',
'ABC:Detail:PRODUCT-DETAIL',
'ABC:Detail:EVENT-LOG',
'ABC:Detail:ORDERS']

result = a.map { |action| action.split(":") }.group_by(&:shift)
result.each do |k1,v1|
  result[k1] = v1.group_by(&:shift)
  result[k1].each { |k2,v2| result[k1][k2] = v2.flatten }
end 

p result 

{"ABC"=>{"Actions"=>["ADD-DATA", "TRANSFER-DATA", "EXPORT", "PRINT"], "Detail"=>["OVERVIEW", "PRODUCT-DETAIL", "EVENT-LOG", "ORDERS"]}}