问UrlGenerationError缺少必需的键[:id]错误？
EN

Stack Overflow用户

提问于 2016-08-26 01:56:54

回答 2查看 1.2K关注 0票数 1

当我想要创建一篇文章时，单击“创建文章”按钮后会得到此错误。

没有路由匹配{：action=>“显示”，：controller=>“项目”，:id=>nil}缺少必需的键：:id

尽管我确保在创建文章之前有一个登录的用户。这是我的密码：

articles_controller.rb

class ArticlesController < ApplicationController
  before_action :require_user , except:[:index,:show]

  def index
      @articles = Article.all
  end  

  def new
    @article = Article.new
  end

  def create
    @article = Article.new(article_params)
    if @article.save
        flash[:notice] = "Your Article was Created"
    else
        render 'new'
    end
    redirect_to article_path(@article)
  end

  def show
    @article = Article.find(params[:id])
  end

  def edit
    @article = Article.find(params[:id])
  end

  def update
    @article = Article.find(params[:id])
    if @article.update(article_params)
        flash[:notice] = "Your Article was Updated"
        redirect_to article_path(@article)
    else
        render 'edit'
    end
  end

  def destroy
    @article = Article.find(params[:id])
    @article.destroy
    flash[:notice] = "Your Article was deleted"
    redirect_to articles_path(@article)
  end

  private

  def article_params
    params.require(:article).permit(:title,:description)
  end

结束

users_controller.rb

class UsersController < ApplicationController
  def index
    @users = User.all
  end

  def new
    @user = User.new
  end

  def create
    @user = User.new(user_params)
    if @user.save
      flash[:success] = "You Signed up successfully"
      redirect_to articles_path
    else
      render 'new'
    end
  end

  def show
    @user = User.find(params[:id])
  end

  def edit
    @user = User.find(params[:id])
  end

  def update
    @user = User.find(params[:id])
    if @user.update(user_params)
      flash[:success]= "Your user was updated"
      redirect_to articles_path
    else
      render 'edit'
    end
  end

  private

  def user_params
    params.require(:user).permit(:username,:email,:password)
  end

结束

views/new.html

    <h1>New Article</h1>
<%= form_for @article do |f| %>

<p>title<%= f.text_field :title %></p><br>
<p>description<%= f.text_area :description %></p>
<%= f.submit "Create" %>
<%end%>

这是我的github回购

ruby-on-rails

ruby

ruby-on-rails-3

ruby-on-rails-4

ruby-on-rails-3.2

回答 2

Stack Overflow用户

回答已采纳

发布于 2016-08-26 02:34:32

当您创建一个无效的文章时，它将给您missing required keys: [:id]，因为它失败了@article.save，它将redirect_to article_path(@article)，在本例中，@article.id是nil

def create
    @article = Article.new(article_params)
    if @article.save
        flash[:notice] = "Your Article was Created"
    else
        render 'new'
    end
    redirect_to article_path(@article)
end

如果redirect_to article_path(@article)是真的，只需移动@article.save即可。

def create
   @article = Article.new(article_params)
   if @article.save
       flash[:notice] = "Your Article was Created"
       redirect_to article_path(@article)
    else
       render 'new'
    end       
end

编辑：

我克隆了您的回购程序，在不使用user_id的情况下创建这篇文章时存在问题。添加了底部的变化，它似乎正在发挥作用，如预期。

def create
       @article = current_user.articles.build(article_params)

       if @article.save
           flash[:notice] = "Your Article was Created"
           redirect_to article_path(@article)
        else
           render 'new'
        end       
    end

希望这能帮上忙！

票数 2

Stack Overflow用户

发布于 2016-08-26 02:45:43

您得到了这个错误，因为呈现和重定向都在@article.save fails.So中被执行--在其他部分，它将呈现为新的，并再次重定向以id = nil显示页面。

def create
   @article = Article.new(article_params)
   if @article.save
       flash[:notice] = "Your Article was Created"
       redirect_to article_path(@article.id) # or @article
    else
       render 'new'
    end       
end