ruby-on-rails - 如何调试未定义的方法 form_with 错误

Question

我收到错误:
undefined form_with for #<#<Class:0x7ac62e0>:0x551e5a8>
in articles#new
错误发生在以下文件中:new.html.erb其中有:

<%= form_with(model: [@article] , local: true) do |f| %>
  <p>
    <%= f.label :title %><enter code here`br>
    <%= f.text_field :title %>
  </p>

和 Controller articles_controller.rb已:

class ArticlesController < ApplicationController
  def new
  end
end

Answer 1

您的 Controller 只有新命令，请参阅下面的示例以创建实例变量 @article

文章_controller.rb

class ArticlesController < ApplicationController 
  def new
    @article = Article.new
  end
end

新的.html.erb

<%= form_with @article do |f| %>
  <%= f.label "Enter title: " %> 
  <%= f.text_field :title %> 
<% end %>