时间戳

首页 > 解决方案 > Ruby on Rails 为下拉值创建方法“未初始化的常量”错误

ruby-on-rails - Ruby on Rails 为下拉值创建方法“未初始化的常量”错误

问题描述

我有一个表单可以正确呈现并在我的服务器日志中产生正确的值，但是当我去创建实际对象时它遇到了错误。

该模型被调用LeadMagnet，这是架构：

  create_table "lead_magnets", force: :cascade do |t|
    t.string "title"
    t.text "description"
    t.boolean "motivation", default: false
    t.boolean "mindset", default: false
    t.boolean "resourcing", default: false
    t.boolean "planning", default: false
    t.boolean "time_management", default: false
    t.boolean "discipline", default: false
    t.string "type"
    t.string "link_url"
    t.boolean "active", default: true
    t.bigint "user_id"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.index ["user_id"], name: "index_lead_magnets_on_user_id"
  end

lead_magnet#create在这一行的我的方法上调用了错误：

@lead_magnet = LeadMagnet.new(lead_magnet_params)

这是它所指的参数：

def lead_magnet_params
  params.require(:lead_magnet).permit(
    :title,
    :description,
    :motivation,
    :mindset,
    :resourcing,
    :planning,
    :time_management,
    :discipline,
    :type,
    :link_url,
    :active,
    :user_id
  )
end

问题在于“type”的值，它是由以下代码生成的字符串：

  <div class="form-group col-12 mb-0 pb-0">
    <%= f.input :type, label: false, prompt: "Select LM Type", input_html: { class: 'mdb-select md-form colorful-select' }, collection: [['Attachment', 'Attachment'], ['Link', 'Link']], required: true %>
  </div>

这反过来在服务器日志中创建：

Started POST "/lead_magnets" for ::1 at 2019-10-05 21:11:07 -0700
Processing by LeadMagnetsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"3NYnrPxC6oucYnV25TFOnAmbLjDoRLRisLkbNaisDBV6yCLkg1yXPC6bUo2hzEkrML1VdH+4BY4iLbqgGs0nIg==", "lead_magnet"=>{"title"=>"", "description"=>"", "motivation"=>"0", "mindset"=>"0", "resourcing"=>"0", "planning"=>"0", "time_management"=>"0", "discipline"=>"0", "type"=>"Link", "link_url"=>"", "active"=>"1"}, "commit"=>"Save"}
Completed 500 Internal Server Error in 3ms (ActiveRecord: 0.0ms)



NameError - uninitialized constant Link:
  app/controllers/lead_magnets_controller.rb:27:in `create'

为什么值“Link”在它应该只是一个字符串值时作为一个未初始化的常量出现？

标签： ruby-on-rails

解决方案

事实证明，“type”在 Rails 中是一个受保护的名称。我将列名更改为lead_magnet_type，错误消失了。

推荐阅读