目前，管理员可以创建一个仅上传一个图像的作业。我试图让管理员上传多个文件/图像供用户在作业显示页面上查看。我已经看到了实现这一目标的其他方法，但我无法找到一种方法将其实现到我的应用程序中而不会破坏它。
controller：assignments_controller.rb
class AssignmentsController < ApplicationController
before_action :authenticate_user!
before_filter :admin_access, only: [:new, :create, :edit, :update, :destroy]
def index
@assignments = Assignment.all.order("created_at DESC")
end
def show
@assignment = Assignment.find(params[:id])
end
def new
@assignment = Assignment.new
end
def create
@assignment = current_user.assignments.build
@assignment.name = params[:assignment][:name]
@assignment.description = params[:assignment][:description]
@assignment.picture = params[:assignment][:picture]
if @assignment.save
flash[:notice] = "Assignment was saved successfully."
redirect_to @assignment
else
flash.now[:alert] = "Error creating assignment. Please make sure there is a name and description."
render :new
end
end
def edit
@assignment = Assignment.find(params[:id])
end
def update
@assignment = Assignment.find(params[:id])
@assignment.name = params[:assignment][:name]
@assignment.description = params[:assignment][:description]
@assignment.picture = params[:assignment][:picture]
if @assignment.save
flash[:notice] = "Assignment was updated successfully."
redirect_to @assignment
else
flash.now[:alert] = "Error saving assignment. Please try again."
render :edit
end
end
def destroy
@assignment = Assignment.find(params[:id])
if @assignment.destroy
flash[:notice] = "\"#{@assignment.name}\" was deleted successfully."
redirect_to action: :index
else
flash.now[:alert] = "There was an error deleting the assignment."
render :show
end
end
private
def assignment_params
params.require(:assignment).permit(:name, :description, :picture)
end
end
型号：assignment.rb
class Assignment < ActiveRecord::Base
has_many :submits, dependent: :destroy
belongs_to :user
validates :name, length: { minimum: 1, maximum:120 }
validates :description, length: { minimum: 1 }
mount_uploader :picture, AssignmentpicUploader
end
提交模型/控制器将学生作业提交给管理员
控制器：提交
class SubmitsController < ApplicationController
before_action :authenticate_user!
load_and_authorize_resource param_method: :my_sanitizer
load_and_authorize_resource :through => :current_user
def index
@submits = Submit.all.order("created_at DESC")
end
def show
@submit = Submit.find(params[:id])
end
def new
@submit = current_user.submits.build
end
def create
@submit = current_user.submits.build(submit_params)
if @submit.save
redirect_to submits_path, notice: "The assignment #{@submit.name} has been uploaded."
else
render "new"
end
end
def destroy
@submit = Submit.find(params[:id])
@submit.destroy
redirect_to submits_path, notice: "The assignment #{@submit.name} has been deleted."
end
private
def submit_params
params.require(:submit).permit(:name, :attachment)
end
end
型号：submit.rb
class Submit < ActiveRecord::Base
belongs_to :assignment
belongs_to :user
validates :name, presence: true # Make sure the owner's name is present.
mount_uploader :attachment, AttachmentUploader # Tells rails to use this uploader for this model.
end
上传者：assignmentpic_uploader.rb
# encoding: utf-8
class AssignmentpicUploader < CarrierWave::Uploader::Base
include CarrierWave::MiniMagick
storage :file
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
# Create different versions of your uploaded files:
version :large do
process :resize_to_fit => [500, 700]
end
# Add a white list of extensions which are allowed to be uploaded.
def extension_white_list
%w(jpg jpeg gif png)
end
end
视图/分配：
edit.html.erb
<h1>Edit Assignment</h1>
<div class="row">
<div class="col-md-4">
<p>Guidelines for topics:</p>
<ul>
<li>Make sure the topic is appropriate.</li>
<li>Never insult dogs.</li>
<li>Smile when you type.</li>
</ul>
</div>
<div class="col-md-8">
<%= form_for @assignment do |f| %>
<div class="form-group">
<%= f.label :name %>
<%= f.text_field :name, class: 'form-control', placeholder: "Enter assignment name" %>
</div>
<div class="form-group">
<%= f.label :description %>
<%= f.text_area :description, rows: 8, class: 'form-control', placeholder: "Enter assignment description" %>
</div>
<div class="form-group">
<%= f.label :picture %>
<%= f.file_field :picture %>
</div>
<br />
<%= f.submit "Save", class: 'button' %>
<% end %>
</div>
</div>
index.html.erb
<div class="col-lg-12 text-center">
<h1>Assignments
<% if current_user.admin %>
<%= link_to "New Assignment", new_assignment_path, class: 'btn btn-success' %>
<% end %>
<hr>
</h1>
</div>
<div class="row">
<div class="col-md-10">
<!-- #7 -->
<% @assignments.each do |assignment| %>
<div class="media">
<div class="media-body">
<h3 class="media-heading">
<!-- #8 <-->
<%= link_to assignment.name, assignment %>
</h3>
<!-- Date/Time -->
<p><span class="glyphicon glyphicon-time"></span>
<%= time_ago_in_words(assignment.created_at) %> ago
</p>
<small>
<%= assignment.description %>
</small>
</div>
</div>
<hr>
<% end %>
</div>
<br>
</div>
new.html.erb
<h1>New Assignment</h1>
<div class="row">
<div class="col-md-4">
<p>Guidelines for topics:</p>
<ul>
<li>Make sure the topic is appropriate.</li>
<li>Never insult dogs.</li>
<li>Smile when you type.</li>
</ul>
</div>
<div class="col-md-8">
<%= form_for @assignment do |f| %>
<div class="form-group">
<%= f.label :name %>
<%= f.text_field :name, class: 'form-control', placeholder: "Enter assignment name" %>
</div>
<div class="form-group">
<%= f.label :description %>
<%= f.text_area :description, rows: 8, class: 'form-control', placeholder: "Enter assignment description" %>
</div>
<div class="form-group">
<%= f.label :picture %>
<%= f.file_field :picture %>
</div>
<br />
<%= f.submit "Save", class: 'button' %>
<% end %>
</div>
</div>
show.html.erb
<h1><%= @assignment.name %>
<% if current_user.admin %>
<%= link_to "Edit Assignment", edit_assignment_path, class: 'btn btn-success btn-sm round' %>
<%= link_to "Delete Assignment", @assignment, method: :delete, class: 'btn btn-danger btn-sm round ', data: { confirm: 'Are you sure you want to delete this assignment?' } %>
<% end %>
</h1>
<div class="row">
<div class="col-md-8">
<p class="lead"><%= @assignment.description %></p>
<!-- #10 -->
<% @assignment.submits.each do |submit| %>
<div class="media">
<div class="media-body">
<h4 class="media-heading">
<%= link_to submit.name, submit %>
</h4>
</div>
</div>
<% end %>
</div>
<div id="img">
<%= image_tag @assignment.picture.url(:large) %>
</div>
</br>
<div class="col-md-4">
<%= link_to "Submit Assignment", new_submit_path(@assignment), class: 'button' %>
</div>
</div>
视图/提交：
index.html.erb
<div class="col-lg-12 text-center">
<h1>Student Work</h1>
<hr>
</div>
<% if current_user.admin %>
<small>Hold "CTRL" + "F" to search for assignment or student name.</small>
<% end %>
<br />
<br />
<table class = "table table-bordered table-striped">
<thead>
<tr>
<th>Name</th>
<th>View Assignments</th>
<th>Delete</th>
</tr>
</thead>
<tbody>
<% @submits.each do |submit| %>
<tr>
<% if can? :destroy, submit %>
<td><%= submit.name %></td>
<td><%= link_to "View Assignment", submit.attachment_url %></td>
<td><%= button_to "Delete", submit, method: :delete, class: "button", data: { confirm: "Are you sure that you wish to delete #{submit.name}?" } %></td>
<% end %>
</tr>
<% end %>
</tbody>
</table>
new.html.erb
<div class="text-center">
<h1>Submit Assignment</h1>
</div>
<hr>
<% if !@submit.errors.empty? %>
<div class = "alert alert-error">
<ul>
<% @submit.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class = "well">
<%= form_for @submit, html: { multipart: true } do |f| %>
<%= f.label :name %>
<%= f.text_field :name %>
<br />
<%= f.label :attachment %>
<%= f.file_field :attachment %>
<br />
<%= f.submit "Save", class: "button" %>
<% end %>
</div>
<p>Please include "ASSIGNMENT NAME - YOUR NAME" in the field above</p>
<br />
<p> Example:</p>
<small> assignment 1 - Bob Smith</small>
schema.rb
# encoding: UTF-8
# This file is auto-generated from the current state of the database. Instead
# of editing this file, please use the migrations feature of Active Record to
# incrementally modify your database, and then regenerate this schema definition.
#
# Note that this schema.rb definition is the authoritative source for your
# database schema. If you need to create the application database on another
# system, you should be using db:schema:load, not running all the migrations
# from scratch. The latter is a flawed and unsustainable approach (the more migrations
# you'll amass, the slower it'll run and the greater likelihood for issues).
#
# It's strongly recommended that you check this file into your version control system.
ActiveRecord::Schema.define(version: 20160930021506) do
create_table "articles", force: :cascade do |t|
t.string "title"
t.text "body"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "user_id"
end
create_table "assignments", force: :cascade do |t|
t.string "name"
t.text "description"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "user_id"
t.string "picture"
end
add_index "assignments", ["user_id"], name: "index_assignments_on_user_id"
create_table "clients", force: :cascade do |t|
t.string "name"
t.string "email"
t.text "message"
t.datetime "created_at"
t.datetime "updated_at"
t.string "phone"
end
create_table "comments", force: :cascade do |t|
t.text "body"
t.integer "user_id"
t.integer "article_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
add_index "comments", ["article_id"], name: "index_comments_on_article_id"
add_index "comments", ["user_id"], name: "index_comments_on_user_id"
create_table "contacts", force: :cascade do |t|
t.string "name"
t.string "email"
t.text "message"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "submits", force: :cascade do |t|
t.string "name"
t.string "attachment"
t.integer "assignment_id"
t.integer "user_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "users", force: :cascade do |t|
t.string "username", default: "", null: false
t.string "email", default: "", null: false
t.string "encrypted_password", default: "", null: false
t.string "reset_password_token"
t.datetime "reset_password_sent_at"
t.datetime "remember_created_at"
t.integer "sign_in_count", default: 0, null: false
t.datetime "current_sign_in_at"
t.datetime "last_sign_in_at"
t.string "current_sign_in_ip"
t.string "last_sign_in_ip"
t.string "confirmation_token"
t.datetime "confirmed_at"
t.datetime "confirmation_sent_at"
t.string "unconfirmed_email"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.boolean "admin", default: false
t.string "firstname"
t.string "lastname"
end
add_index "users", ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
add_index "users", ["email"], name: "index_users_on_email", unique: true
add_index "users", ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
end
对不起，如果信息太多或太少。 也提前感谢你们这里所有精彩的人都愿意伸出援助之手。