Ruby on rails 如果URL包含字符串？

如果

：name

被传递到_表单，我如何使用条件来做一件事，如果

：name

没有被传递，如何使用条件来做另一件事

通过

：name

：

Started GET "/inspirations/new?inspiration%5Bname%5D=Always+trust+yourself+more+than+you+doubt+yourself" for 127.0.0.1 at 2016-11-08 01:00:44 -0500
Processing by InspirationsController#new as HTML
  Parameters: {"inspiration"=>{"name"=>"Always trust yourself more than you doubt yourself"}}

Started GET "/inspirations/new" for 127.0.0.1 at 2016-11-08 01:16:18 -0500
Processing by InspirationsController#new as */*
  User Load (0.3ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
  CACHE (0.0ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
  Inspiration Load (0.4ms)  SELECT  "inspirations".* FROM "inspirations" WHERE "inspirations"."id" IS NULL LIMIT 1
  Rendered inspirations/_form.html.erb (4.1ms)
  Rendered inspirations/new.html.erb within layouts/modal (5.9ms)
Completed 200 OK in 49ms (Views: 41.9ms | ActiveRecord: 0.7ms)

无

：传递了名称
：

Started GET "/inspirations/new?inspiration%5Bname%5D=Always+trust+yourself+more+than+you+doubt+yourself" for 127.0.0.1 at 2016-11-08 01:00:44 -0500
Processing by InspirationsController#new as HTML
  Parameters: {"inspiration"=>{"name"=>"Always trust yourself more than you doubt yourself"}}

Started GET "/inspirations/new" for 127.0.0.1 at 2016-11-08 01:16:18 -0500
Processing by InspirationsController#new as */*
  User Load (0.3ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
  CACHE (0.0ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
  Inspiration Load (0.4ms)  SELECT  "inspirations".* FROM "inspirations" WHERE "inspirations"."id" IS NULL LIMIT 1
  Rendered inspirations/_form.html.erb (4.1ms)
  Rendered inspirations/new.html.erb within layouts/modal (5.9ms)
Completed 200 OK in 49ms (Views: 41.9ms | ActiveRecord: 0.7ms)

_形式


#如果URL中不存在名称，则应触发
等

例如，当URL包含字符串时：

http://www.livetochallenge.com/inspirations/new?inspiration%5Bname%5D=Life+如果+我+有+源代码+代码，会更简单。

但我经常使用URL缩短器

不适合我：




试试这个：

<%= simple_form_for(@inspiration) do |f| %> 
  <%= f.text_area :name %>
  <% if params[:inspiration].try(:[], :name).nil? %> # Should Be Triggered If No :name Is Present in URL
    etc...
  <% end %>
<% end %>


#如果URL中不存在名称，则应触发
等

仅当存在后面的参数时，才会检查参数[：inspiration]中的：name。因此，不应出现错误。
您可以使用避免错误


等
你试过
参数[:inspiration][:name]
而不是
参数[:name]
吗？啊，我试过
：inspiration\u name
，但不是那样。我想这可能行得通，但我得到了一个
ActionView:：Template:：Error（nil:NilClass的未定义方法“[]”）：
Error。你能提供一个答案，这样我就可以给你@Pavan评分了吗？
params[：inspiration][：name]
触发了这个错误？Yea@Pavan。我明白了。谢谢你的帮助！