创建

Question

我是rails的新手，我试图创建一个表单来将角色与用户关联，我在表单中有两个collection_select，但是当我想创建或更新时，我收到此错误：

我的控制器代码是：

class UserRolesController < ApplicationController
 before_action :set_user_role, only: [:show, :edit, :update, :destroy]
 @@roles =RolesController.new 
 @@users =UsersController.new 
 # GET /user_roles
 # GET /user_roles.json
 def index
 @user_roles = UserRole.all
 end

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

 # GET /user_roles/new
 def new
  @user_role = UserRole.new
  @users =@@users.get_all_users
  @roles =@@roles.get_all_roles
 end

 # GET /user_roles/1/edit
 def edit
   @users =@@users.get_all_users
   @roles =@@roles.get_all_roles
   @user_roles =UserRole.find(params[:id])
   @selected_role=@user_roles.role_id
   @selected_user=@user_roles.user_id  
end

# POST /user_roles
# POST /user_roles.json
def create
  @user_role = UserRole.new(user_role_params)
  respond_to do |format|
   if @user_role.save
        format.html { redirect_to @user_role, notice: 'User role was   successfully created.' }
        format.json { render :show, status: :created, location: @user_role }
   else
     format.html { render :new }
     format.json { render json: @user_role.errors, status: :unprocessable_entity }
   end
 end
end



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

 # DELETE /user_roles/1
 # DELETE /user_roles/1.json
   def destroy
   @user_role.destroy
   respond_to do |format|
   format.html { redirect_to user_roles_url, notice: 'User role was successfully destroyed.' }
   format.json { head :no_content }
  end
 end

 def get_user_role_by_userid(user_id)
   return UserRole.where(user_id:user_id).first
 end
 private
   # Use callbacks to share common setup or constraints between actions.
   def set_user_role
    @user_role = UserRole.find(params[:id])
  end

   # Never trust parameters from the scary internet, only allow the white list through.
  def user_role_params
    params.require(:user_role).permit(:role_id,:user_id)
  end

端

我的表单代码是：

<%= form_for(user_role) do |f| %>
  <% if user_role.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(user_role.errors.count, "error") %> prohibited this user_role from being saved:</h2>

      <ul>
        <% user_role.errors.full_messages.each do |message| %>
          <li><%= message %></li>
        <% end %>
      </ul>
    </div>
  <% end %>
  <div class="field">
    <%= f.label :user %>
    <%= collection_select(:user_id, :user_id,@users, :id, :name,{:selected => @selected_user}) %>
  </div>

  <div class="field">
    <%= f.label :rol %>
    <%= collection_select(:role_id, :role_id,@roles, :id, :role {:selected => @selected_role}) %>
  </div>

  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

我做错了什么？ ，在这种情况下我如何设置user_role_params？ 我使用的是ruby 2.3.1和Rails：5.0.1

感谢您的建议。

Answer 1

您需要在收集集之前放置一个f：

<%= form_for(user_role) do |f| %>
 <% if user_role.errors.any? %>
  <div id="error_explanation">
   <h2><%= pluralize(user_role.errors.count, "error") %> prohibited this user_role from being saved:</h2>

   <ul>
    <% user_role.errors.full_messages.each do |message| %>
      <li><%= message %></li>
    <% end %>
   </ul>
  </div>
 <% end %>
 <div class="field">
 <%= f.label :user %>
 <%= f.collection_select(:user_id, @users, :id, :name,{:selected => @selected_user}) %>
</div>

<div class="field">
 <%= f.label :rol %>
 <%= f.collection_select(:role_id, @roles, :id, :role {:selected => @selected_role}) %>
</div>

<div class="actions">
 <%= f.submit %>
</div>

   

否则，params会像user_id而不是user_role[user_id]

一样发送