Question

我最终得到了10个CSV :: Row对象的数组。现在我想配对它们，因为每个对象中有2个具有相同的名称。现在我知道如何做到这一点，多循环的方式，它只是不优雅。任何人都有快速的1-2班轮来做这件事吗？

所以这是数组：

[#<CSV::Row "name":"eee.xxx" "time":"2014-10-31T15:35:14+00:00" "records":"98">,
 #<CSV::Row "name":"eee.yyy" "time":"2014-10-31T15:35:30+00:00" "records":"207">,
 #<CSV::Row "name":"sss.zzz" "time":"2014-10-31T15:35:44+00:00" "records":"205">,
 #<CSV::Row "name":"sss.qqq" "time":"2014-10-31T15:35:59+00:00" "records":"220">,
 #<CSV::Row "name":"sss.www" "time":"2014-10-31T15:36:15+00:00" "records":"220">,
 #<CSV::Row "name":"eee.xxx" "time":"2014-10-31T15:36:30+00:00" "records":"99">,
 #<CSV::Row "name":"eee.yyy" "time":"2014-10-31T15:36:42+00:00" "records":"210">,
 #<CSV::Row "name":"sss.zzz" "time":"2014-10-31T15:36:57+00:00" "records":"225">,
 #<CSV::Row "name":"sss.qqq" "time":"2014-10-31T15:37:12+00:00" "records":"210">,
 #<CSV::Row "name":"sss.www" "time":"2014-10-31T15:37:25+00:00" "records":"230">]

我希望最终得到像这样的哈希：

{"eee.xxx" => [98,99],
 "eee.yyy" => [207,210],
 "sss.zzz" => [205,225],
 "sss.qqq" => [220,210],
 "sss.www" => [220,203]}

有什么想法吗？

Answer 1

是的，如下所示： -

hash = array.each_with_object(Hash.new { |h,k| h[k] = [] }) do |row,hsh| 
  hsh[row['name']] << row['records']
end

查看方法CSV::Row#[]和new {|hash, key| block } → new_hash方法。

另一种方式是： -

hash = array.each_with_object({}) do |row,hsh| 
  (hsh[row['name']] ||= []) << row['records']
end

配对CSV :: Row对象

1 个答案: