Question

NoMethodError（未定义的方法projects' for nil:NilClass): app/controllers/project_controller.rb:8:in索引＆＃39;

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/Users/ajaysithagari/.rvm/gems/ruby-2.2.1/gems/web-console-2.2.1/lib/web_console/templates/main.js.erb
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/Users/ajaysithagari/.rvm/gems/ruby-2.2.1/gems/web-console-2.2.1/lib/web_console/templates/index.html.erb (116.8ms)

这是一个项目控制器：

class ProjectController < ApplicationController

  before_action :confirm_logged_in

  before_action :find_company


  def index

    @projects = @company.projects.sorted
  end

  def show

    @project = Project.find(params[:id])
  end

  def new

    @project = Project.new()
    @project_count = Project.count + 1
    @companys = Company.order("position ASC")
  end

  def create

    @project = Project.new(project_params)
    if @project.save
      redirect_to(:action => 'index')
    else

      @project_count = Project.count + 1
      @companys = Company.order("position ASC")
      render('new')
    end
  end

  def edit

    @project = Project.find(params[:id])
    @project_count = Project.count 
    @companys = Company.order("position ASC")
  end

  def update

    @project = Project.find(params[:id])
    if @project.update_attributes(project_params)
      redirect_to(:action => 'index')
    else

      @project_count = Project.count
      @companys = Company.order("position ASC")
      render('new')
    end
  end

  def delete

    @project = Project.find(params[:id])
  end

  def destory

    @project = Project.find(params[:id])
    @project.destroy
    redirect_to(:action => 'index')
  end


  private 

  def project_params

   params.require(:project).permit(:name, :position, :type_of_project, :description, :no_of_tasks)
  end

  def find_company

    if params[:company_id]
      @company = Company.find(params[:company_id])
    end
  end
end

Answer 1

错误表示@company为nil。公司来自方法find_company，您可以更正find_company逻辑，也可以在请求中提供company_id参数。如果index为零，您还可以调整@company方法以获取所有项目：

def index
  @projects = Project.all.sorted
end

这完全取决于您希望如何加载项目。

Answer 2

您的链接网址或按钮网址是指索引页面的内容。您需要通过:company_id参数才能使其正常工作。

e.g。

projects_path(:company_id => Company.first.id)

NoMethodError（未定义的方法`projects＆＃39; for nil：NilClass）：

2 个答案: