ruby-on-rails - 强参数 : Hash param is missing or the value is empty

Question

我有一个表单，其中有一个带有复选框的表格，以便选择行并将 ID 保存在我的数据库中。

但它抛出一个错误:

Param is missing or the value is empty: leadallocation"

我尝试了不同的方法，但仍然没有效果。所以目前我只想将哈希保存在我的数据库中。谢谢。

# Never trust parameters from the scary internet, only allow the white list through.
def leadallocation_params
  params.require(:leadallocation).permit(:campaign_id, :company_id, :user_id)
end

请求参数:

{"utf8"=>"✓",
 "authenticity_token"=>"GruGL758jT4FO+t/BTRGLrD2uCGOj/qUCrB5VswquzR9N7JZ/rouLmGZnTE7A+XTARiLwkOy1n3/zMqhzuenmg==",
 "company_ids"=>["38",
 "40"],
 "commit"=>"Create Leadallocation"}

Controller

class LeadallocationsController < ApplicationController
  before_action :set_leadallocation, only: [:show, :edit, :update, :destroy]

  # GET /leadallocations
  # GET /leadallocations.json
  def complete
  end


  def index
    @leadallocations = Leadallocation.all
  end

  # GET /leadallocations/1
  # GET /leadallocations/1.json
  def show
  end

  # GET /leadallocations/new
  def new


    @leadallocation = Leadallocation.new
    @comps =  Company.all
  end

  # GET /leadallocations/1/edit
  def edit
  end

  # POST /leadallocations
  # POST /leadallocations.json
  def create

    @leadallocation = Leadallocation.new(leadallocation_params)

    @leadallocation.company_id = params[:company_ids]


    respond_to do |format|
      if @leadallocation.save
        format.html { redirect_to @leadallocation, notice: 'Leadallocation was successfully created.' }
        format.json { render :show, status: :created, location: @leadallocation }
      else
        format.html { render :new }
        format.json { render json: @leadallocation.errors, status: :unprocessable_entity }
      end
    end
  end

  # PATCH/PUT /leadallocations/1
  # PATCH/PUT /leadallocations/1.json
  def update
    respond_to do |format|
      if @leadallocation.update(leadallocation_params)
        format.html { redirect_to @leadallocation, notice: 'Leadallocation was successfully updated.' }
        format.json { render :show, status: :ok, location: @leadallocation }
      else
        format.html { render :edit }
        format.json { render json: @leadallocation.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /leadallocations/1
  # DELETE /leadallocations/1.json
  def destroy
    @leadallocation.destroy
    respond_to do |format|
      format.html { redirect_to leadallocations_url, notice: 'Leadallocation was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_leadallocation
      @leadallocation = Leadallocation.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def leadallocation_params
      params.require(:leadallocation).permit(:campaign_id, :company_id, :user_id)
    end
end

模型

class Leadallocation < ActiveRecord::Base
  belongs_to :campaign
  belongs_to :company
  belongs_to :user
end

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  has_many :activities
  belongs_to :campaign
  has_many :leadallocations

  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable
end

class Company < ActiveRecord::Base
  belongs_to :campaign
  has_many :subsidiaries
  has_many :leadallocations
end

class Campaign < ActiveRecord::Base
  belongs_to :client
  has_many :leads
  has_many :activities
  has_many :contacts
  has_many :users
has_many :leadallocations

end

路线.rb

resources :leadallocations

景色

    <h1>New Leadallocation</h1>

<p id="notice"><%= notice %></p>

<h1>Listing Companies</h1>
<%= simple_form_for(@leadallocation) do |f| %>

<table class="table table-bordered">
  <thead>
    <tr>
      <th></th>
      <th>Name</th> 
      <th>Country</th>
      <th colspan="3"></th>
    </tr>
  </thead>

  <tbody>
    <% @comps.each do |company| %>
      <tr>
      <td><%= check_box_tag "company_ids[]", company.id %></td>
        <td><%= company.name %></td>
        <td><%= company.country %></td>

      </tr>
    <% end %>
  </tbody>
</table>

<br>
<div class="form-actions">
    <%= f.button :submit %>
  </div>
<% end %>
<%= link_to 'Back', leadallocations_path %>

Answer 1

您使用强参数的方式要求您的参数遵循特定的形式。

在这种情况下，您的参数需要嵌套在键 leadallocation 下

问题出在您的表单中，而不是check_box_tag，您需要执行f.check_box 并使用this documentation查看可用选项。

这会将您的属性嵌套在 leadallocation 下，如果没有嵌套，则您的模型和表单设置可能有问题。

基本上所有这些都是说你想改变你的参数:

 {"utf8"=>"✓",
  "authenticity_token"=>"GruGL758jT4FO+t/BTRGLrD2uCGOj/qUCrB5VswquzR9N7JZ/rouLmGZnTE7A+XTARiLwkOy1n3/zMqhzuenmg==",
  "company_ids"=>["38",
  "40"],
  "commit"=>"Create Leadallocation"}

为此:

 {"utf8"=>"✓",
  "authenticity_token"=>"GruGL758jT4FO+t/BTRGLrD2uCGOj/qUCrB5VswquzR9N7JZ/rouLmGZnTE7A+XTARiLwkOy1n3/zMqhzuenmg==",
  "leadallocation" => {
    "company_ids"=>["38","40"]
  }
  "commit"=>"Create Leadallocation"}