立即在Ruby的Rails上为所有用户创建出勤率

Question

我必须以下模型：

class User < ActiveRecord::Base
  has_many  :addresses
  has_many  :enrollments
  has_many  :courses, :through => :enrollments
  has_many  :attendances
  has_many  :lessons, :through => :courses

class Enrollment < ActiveRecord::Base
  belongs_to :user
  belongs_to :course

class Course < ActiveRecord::Base
  has_many  :enrollments
  has_many  :users, :through => :enrollments
  has_many  :lessons
  has_many  :attendances, :through => :lessons
class Lesson < ActiveRecord::Base
  belongs_to :course
  has_many :attendances
  has_many :users, through: :course
class Attendance < ActiveRecord::Base
  belongs_to :user
  belongs_to :lesson

，在我的出勤控制器中，我有：

class AttendancesController < ApplicationController
  before_filter :set_lesson
def new
    @attendance = @lesson.attendances.new
end
def create
    #@attendance = Attendance.new(attendance_params)
    @attendance = @course.attendances.new(params[:milestone])
    respond_to do |format|
      if @attendance.save
        format.html { redirect_to @attendance, notice: 'Attendance was successfully created.' }
        format.json { render :show, status: :created, location: @attendance }
      else
        format.html { render :new }
        format.json { render json: @attendance.errors, status: :unprocessable_entity }
      end
    end
end
def set_lesson
   @course = Course.find(params[:course_id]) 
   @lesson = @course.lessons.find(params[:lesson_id])
end

我的嵌套路线：

Rails.application.routes.draw do
  #resources :attendances
  resources :courses do
    resources :lessons do
      resources :attendances
    end
    resources :enrollments
    end

我想实现的目标是为注册到该课程的用户上课。任何建议或帮助使这一可能的建议都将不胜感激。我看到了类似的问题，但是它们与我没有相同的结构。截至目前，当我单击新的出席率时，我只得到一个创建唱片表格，但是我希望它显示每个学生的所有学生名称和出勤领域，因此我可以在盎司时提交全部。我已经尝试了两天，没有运气，所以请帮忙。预先感谢。

create_table "attendances", force: :cascade do |t|
    t.integer  "user_id",    null: false
    t.integer  "lesson_id",  null: false
    t.string   "status",     null: false
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end
  add_index "attendances", ["lesson_id"], name: "index_attendances_on_lesson_id", using: :btree
  add_index "attendances", ["user_id"], name: "index_attendances_on_user_id", using: :btree
  create_table "courses", force: :cascade do |t|
    t.string   "name"
    t.string   "section"
    t.text     "description"
    t.datetime "created_at",  null: false
    t.datetime "updated_at",  null: false
    t.date     "start_date"
    t.date     "end_date"
  end
  create_table "enrollments", force: :cascade do |t|
    t.integer  "user_id"
    t.integer  "course_id"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end
  add_index "enrollments", ["course_id"], name: "index_enrollments_on_course_id", using: :btree
  add_index "enrollments", ["user_id"], name: "index_enrollments_on_user_id", using: :btree
  create_table "homes", force: :cascade do |t|
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end
  create_table "lessons", force: :cascade do |t|
    t.datetime "meeting",               null: false
    t.datetime "end_time",              null: false
    t.string   "subject",    limit: 40, null: false
    t.integer  "course_id"
    t.datetime "created_at",            null: false
    t.datetime "updated_at",            null: false
  end
  add_index "lessons", ["course_id"], name: "index_lessons_on_course_id", using: :btree
  create_table "registrations", force: :cascade do |t|
    t.integer  "user_id",    null: false
    t.integer  "course_id",  null: false
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end

Answer 1

您正在布置相当复杂的关联，我不确定我要遵循您要做的确切过程。无论如何，一旦您了解创建关联记录的基本概念，就应该能够使其适应您的特定情况。

所以，要离开你说的话：

我要实现的是为注册到该课程的用户创建上课。

假设您有以下关联：

• 课程有很多用户
• 课程有很多出勤
• 出勤有一个User_id列

说您有一个lesson_id。

然后您可以写：

lesson = Lesson.find(lesson_id)
users = lesson.users
users.each { |user| lesson.attendances.create(user: user) }

或类似的东西，以便为属于课程的每个用户创建出勤率。