Question

我在创建一个可以保存我的has_many的表单时遇到问题：通过关联。我通过发布json成功保存了，但这些表单对我来说还不行。由表单提交创建的请求参数将无法解决。任何指导我解决方案的帮助都会帮助我失去更多的时间。先谢谢。

已编辑 - 添加了要尝试的表单_以及在底部无法正常工作的已创建的参数json -

Json发布请求参数：

{
    "author": {
        "name": "Author Name",
        "post_authors_attributes": [
          {"post_id":"1"},
          {"post_id":"2"},
          {"post_id":"3"}
        ]
    }
}

Rails会生成无法保存的参数。

{
    "author": {
        "name": "assd",
        "post_authors_attributes": [
            "",
            "2",
            "3"
        ]
    }
}

...以及相关的代码示例......

作者模型

class Author < ActiveRecord::Base
  has_many :post_authors
  has_many :posts, :through => :post_authors
  accepts_nested_attributes_for :post_authors
end

发布模型（目前只在作者上工作有很多帖子，而不是相反的）

class Post < ActiveRecord::Base
end

PostAuthor模型

class PostAuthor < ActiveRecord::Base
  belongs_to :post
  belongs_to :author
end

作者控制器新建/创建操作

  # GET /authors/new
  def new
    @author = Author.new
    @author.post_authors.build
  end

  # POST /authors
  # POST /authors.json
  def create
    @author = Author.new(params)

    respond_to do |format|
      if @author.save
        format.html { redirect_to @author, notice: 'Author was successfully created.' }
        format.json { render :show, status: :created, location: @author }
      else
        format.html { render :new }
        format.json { render json: @author.errors, status: :unprocessable_entity }
      end
    end
  end

作者/ _form.html.erb

<%= form_for(@author) do |f| %>
  <% if @author.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@author.errors.count, "error") %> prohibited this author from being saved:</h2>

      <ul>
      <% @author.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
  </div>

    <%= collection_select(:author, :post_authors_attributes, Post.all, :id, :title,
                                     {include_blank: false, :selected => @author.posts.map(&:id)},
                                     {:multiple => true}) %>

  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

模式

ActiveRecord::Schema.define(version: 20150120190715) do

  create_table "authors", force: :cascade do |t|
    t.string   "name"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end

  create_table "post_authors", force: :cascade do |t|
    t.integer  "post_id"
    t.integer  "author_id"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end

  create_table "posts", force: :cascade do |t|
    t.string   "title"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
  end

end

编辑 - 已添加详细信息 - 只是为了尽职尽责，我也尝试过使用fields_for，但是它会产生更多混乱的json，而不会保存到数据库中。我不知道“0”键来自哪里。我坚持这一点，任何帮助都会非常感激。

fields_for

  <div class="field">
    <%= f.fields_for :post_authors, @author.post_authors do |posts_form| %>
        <%= f.label :Posts %><br>
        <%= posts_form.collection_select(:post_id, Post.all, :id, :title,
                                         {include_blank: false, :selected => @author.posts.map(&:id)},
                                         {:multiple => true}) %>

    <% end %>
  </div>

制作参数to_json

{
    "author": {
        "name": "test",
        "post_authors_attributes": {
            "0": {
                "post_id": [
                    "",
                    "1",
                    "2",
                    "3"
                ]
            }
        }
    }
}

Answer 1

对于遇到同类问题的人，我终于设法使用以下collection_select：

      <%= f.collection_select(:feature_ids, Feature.all, :id, :name,
                              {include_blank: false, :include_hidden => false, :selected => @property.features.map(&:id)},
                              {:multiple => true}) %>

Answer 2

HAVING：

authors/_form.html.erb

<%= fields_for(@author_book) do |ab| %> <div class="field"> <%= ab.label "All Books" %><br> <%= collection_select(:books, :id, @all_books, :id, :name, {:selected => @author.books.map(&:id)}, {multiple: true}) %> </div> <% end %>：

authors_controller.rb

Rails has_many：通过collection_select表单帮助程序

2 个答案: