Ruby on Rails 部分局部變量

Question

在我的網站上，用戶可以參加和重新參加測驗，這意味着我將在部分視圖中使用測驗代碼，編輯視圖和新視圖都將使用該代碼。

為了渲染我在新視圖中的部分：

<%= render partial: "quiz", locals: { url: quiz_bs_path } %>

在我的編輯視圖中：

<%= render partial: "quiz", locals: { url: edit_quiz_b_path } %>

link_to位置來自我的 rake 路線結果：

        quiz_bs GET    /quiz_bs(.:format)             quiz_bs#index
                POST   /quiz_bs(.:format)             quiz_bs#create
     new_quiz_b GET    /quiz_bs/new(.:format)         quiz_bs#new
    edit_quiz_b GET    /quiz_bs/:id/edit(.:format)    quiz_bs#edit
         quiz_b GET    /quiz_bs/:id(.:format)         quiz_bs#show
                PATCH  /quiz_bs/:id(.:format)         quiz_bs#update
                PUT    /quiz_bs/:id(.:format)         quiz_bs#update
                DELETE /quiz_bs/:id(.:format)         quiz_bs#destroy

我在我的編輯視圖中收到一個參數錯誤，說First argument in form cannot contain nil or be empty 。 調用錯誤的行在我的部分：

<%= form_for @quiz_bs, url: url, method: :post do |f| %>

我的控制器代碼是：

class QuizBsController < ApplicationController
before_action :require_sign_in

def show
@quiz_bs = QuizBs.find(params[:id])
end

def new
  @quiz_bs = current_user.quiz_bs || current_user.build_quiz_bs
end

def create
@quiz_bs = QuizBs.new

@quiz_bs.bs01 = params[:quiz_bs][:bs01]
@quiz_bs.bs02 = params[:quiz_bs][:bs02]
@quiz_bs.bs03 = params[:quiz_bs][:bs03]
@quiz_bs.bs04 = params[:quiz_bs][:bs04]
@quiz_bs.bs05 = params[:quiz_bs][:bs05]
@quiz_bs.bs06 = params[:quiz_bs][:bs06]

@quiz_bs.user = current_user

if @quiz_bs.save
  flash[:notice] = "Quiz results saved successfully."
  redirect_to user_path(current_user)
else
  flash[:alert] = "Sorry, your quiz results failed to save."
  redirect_to welcome_index_path
end
end

def update
@quiz_bs = QuizBs.find(params[:quiz_bs])

@quiz_bs.assign_attributes(quiz_bs_params)

if @quiz_bs.save
  flash[:notice] = "Post was updated successfully."
  redirect_to user_path(current_user)
else
  flash.now[:alert] = "There was an error saving the post. Please try again."
  redirect_to welcome_index_path
end
end

private
def quiz_bs_params
  params.require(:quiz_bs).permit(:bs01, :bs02, :bs03, :bs04, :bs05, :bs06)
end

end

模型是：

class QuizBs < ActiveRecord::Base
  before_save :set_bscode

  def set_bscode
    self.bscode = "#{self.bs01}#{self.bs02}#{self.bs03}-#{self.bs04}#{self.bs05}#{self.bs06}"
  end

  belongs_to :user
  validates :user, presence: true
end

我哪里出錯了？

Answer 1

您在控制器中沒有edit操作，因此 rails 假定它為空。 因此@quiz_bs真的nil

添加類似的東西

def edit
  @quiz_bs = QuizBs.find(params[:id])
end

同樣在您的update操作中params[:quiz_bs]也很可能nil ，應該更改為params[:id]

Answer 2

保持簡單，如果你想分配給 current_user， create方法會為你做。

部分的：

#new.html.erb
<%= render partial: "quiz", locals: {quiz: @quiz_bs, url: :quiz_bs } %>


#edit.html.erb
<%= render partial: "quiz", locals: {quiz: @quiz_bs, url: :quiz_b } %>

形式：

#_form.html.erb

<%= form_for quiz, url: url do |f| %>

控制器：

def new
  @quiz_bs = QuisBs.new
end

Answer 3

沒有必要在控制器中創建 RESTfull 方法，但是如果你像我看到的@quiz_bs使用它@quiz_bs那么你必須先初始化它然后你才能使用它，在你的新視圖中你初始化@quiz_bs

@quiz_bs = current_user.quiz_bs || current_user.build_quiz_bs

那么你正在使用它。

並且為edit生成的routes也需要一個id即

edit_quiz_b GET    /quiz_bs/:id/edit(.:format)    quiz_bs#edit

所以你必須通過@quiz_bs

edit_quiz_b_path(@quiz_bs)

知道了？

Answer 4

控制器的一些更新：

before_action :assign_quiz_bs, only: [:show, :edit, :update, :destroy]
#...   
def update
   @quiz_bs.update(quiz_bs_params)

   # .... rendering ...
end

private

def assign_quiz_bs
   @quiz_bs = Quiz.find(params[:id])
end

def quiz_bs_params
   params.require(:quiz_bs).permit(:bs01, :bs02, :bs03, :bs04, :bs05, :bs06)
end