从哈希中拒绝空哈希

Question

我在params中得到了这个哈希 `user_groups_attributes

=> {"0"=>{"name"=>"hello", "id"=>"1", "_destroy"=>"false", "user_ids"=>["201"]},
 "1"=>{"name"=>"hello2", "id"=>"2", "_destroy"=>"false", "user_ids"=>["83"]},
 "2"=>
  {"name"=>"dddddddddd", "id"=>"5", "_destroy"=>"false", "user_ids"=>["256"]},
 "3"=>{"name"=>"", "id"=>"", "_destroy"=>"false"}}`

我需要拒绝所有id =＆＃34;＆＃34;。我怎么能这样做？

Answer 1

hash = {"0"=>{"name"=>"hello", "id"=>"1", "_destroy"=>"false", "user_ids"=>["201"]},
 "1"=>{"name"=>"hello2", "id"=>"2", "_destroy"=>"false", "user_ids"=>["83"]},
 "2"=>
  {"name"=>"dddddddddd", "id"=>"5", "_destroy"=>"false", "user_ids"=>["256"]},
 "3"=>{"name"=>"", "id"=>"", "_destroy"=>"false"}}

hash.reject!{|a, b| b["id"].empty?}
#=> {"0"=>{"name"=>"hello", "id"=>"1", "_destroy"=>"false", "user_ids"=>["201"]}, "1"=>{"name"=>"hello2", "id"=>"2", "_destroy"=>"false", "user_ids"=>["83"]}, "2"=>{"name"=>"dddddddddd", "id"=>"5", "_destroy"=>"false", "user_ids"=>["256"]}}

Answer 2

如果您使用nested_attributes，则可以执行此操作

accepts_nested_attributes_for :user_groups, reject_if: lambda{|attr| attr[:id].blank?} 

我知道你没有在问题或标签中指定Rails，但问题对我来说似乎仍然是Railsy。