Well, I have a params hash like this:
我有一个params散列
params = { :q => { :id_eq => "" } }
What is the best way to test if id_eq is blank? I'm currently using if params[:q] && params[:q][:id_eq].blank? but it seems a lot of duplicated code.
如果id_eq为空，最好的测试方法是什么?我现在使用if params[:q] & params[:q][:::id_eq].blank?但似乎有很多重复的代码。
Is there a better way?
有更好的方法吗?
3 个解决方案
#1
0
if params.fetch(:q, {id_eq: true})[:id_eq].blank?
Comparison between the OP's original code and other answers. So far, my answer is the only one that gives the correct result.
params = { :q => { :id_eq => "" } }
params[:q] && params[:q][:id_eq].blank? # => true (OP)
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => true (my code)
params[:q].try(:[], :id_eq).blank? # => true (Marek Lipka)
params.try(:values_at, :q).first[:id_eq].blank? # => true (mbratch old)
params[:q][:id_eq].blank? rescue false # => true (Doydle)
params.fetch(:q,{})[:id_eq].blank? # => true (Stefan)
params.try(:[], :q).try(:[], :id_eq).blank? # => true (mbratch new)
params = { :q => { :id_eq => "foo" } }
params[:q] && params[:q][:id_eq].blank? # => false
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => false
params[:q].try(:[], :id_eq).blank? # => false
params.try(:values_at, :q).first[:id_eq].blank? # => false
params[:q][:id_eq].blank? rescue false # => false
params.fetch(:q,{})[:id_eq].blank? # => false
params.try(:[], :q).try(:[], :id_eq).blank? # => false
params = {}
params[:q] && params[:q][:id_eq].blank? # => nil (falesy value)
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => false (falesy value)
params[:q].try(:[], :id_eq).blank? # => true # Wrong
params.try(:values_at, :q).first[:id_eq].blank? # => true # Wrong
params[:q][:id_eq].blank? rescue false # => true # Wrong
params.fetch(:q,{})[:id_eq].blank? # => true # Wrong
params.try(:[], :q).try(:[], :id_eq).blank? # => true # Wrong
For the purpose of conditional, the difference between nil and false would not matter, but getting true instead of nil is surely wrong.
出于条件的目的，nil和false之间的区别并不重要，但是用true代替nil肯定是错误的。
#2
4
There is no better way than how you're already doing it. (At least in my opinion.) Relying on exceptions is a bad idea and anything else is significantly less legible.
没有比你已经在做这件事更好的方法了。(至少在我看来是这样。)依赖于例外是一个坏主意，其他任何东西都明显地难以辨认。
#3
-1
rescue is always an option:
救援总是一个选择:
if (params[:q][:id_eq].blank? rescue false)
#1
0
if params.fetch(:q, {id_eq: true})[:id_eq].blank?
Comparison between the OP's original code and other answers. So far, my answer is the only one that gives the correct result.
params = { :q => { :id_eq => "" } }
params[:q] && params[:q][:id_eq].blank? # => true (OP)
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => true (my code)
params[:q].try(:[], :id_eq).blank? # => true (Marek Lipka)
params.try(:values_at, :q).first[:id_eq].blank? # => true (mbratch old)
params[:q][:id_eq].blank? rescue false # => true (Doydle)
params.fetch(:q,{})[:id_eq].blank? # => true (Stefan)
params.try(:[], :q).try(:[], :id_eq).blank? # => true (mbratch new)
params = { :q => { :id_eq => "foo" } }
params[:q] && params[:q][:id_eq].blank? # => false
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => false
params[:q].try(:[], :id_eq).blank? # => false
params.try(:values_at, :q).first[:id_eq].blank? # => false
params[:q][:id_eq].blank? rescue false # => false
params.fetch(:q,{})[:id_eq].blank? # => false
params.try(:[], :q).try(:[], :id_eq).blank? # => false
params = {}
params[:q] && params[:q][:id_eq].blank? # => nil (falesy value)
params.fetch(:q, {id_eq: true})[:id_eq].blank? # => false (falesy value)
params[:q].try(:[], :id_eq).blank? # => true # Wrong
params.try(:values_at, :q).first[:id_eq].blank? # => true # Wrong
params[:q][:id_eq].blank? rescue false # => true # Wrong
params.fetch(:q,{})[:id_eq].blank? # => true # Wrong
params.try(:[], :q).try(:[], :id_eq).blank? # => true # Wrong
For the purpose of conditional, the difference between nil and false would not matter, but getting true instead of nil is surely wrong.
出于条件的目的，nil和false之间的区别并不重要，但是用true代替nil肯定是错误的。
#2
4
There is no better way than how you're already doing it. (At least in my opinion.) Relying on exceptions is a bad idea and anything else is significantly less legible.
没有比你已经在做这件事更好的方法了。(至少在我看来是这样。)依赖于例外是一个坏主意，其他任何东西都明显地难以辨认。
#3
-1
rescue is always an option:
救援总是一个选择:
if (params[:q][:id_eq].blank? rescue false)