如何在Rails 4中以一种形式添加多个多对多字段? [英] How to add multiple many-to-many fields in one form with Rails 4?

问题描述

我有一个具有以下关联的表格:

I have a form that's got the following association:

Course.rb

has_and_belongs_to_many :skills

Skill.rb

has_and_belongs_to_many :courses

我想做的是允许想要添加新Course的人从所选类别中选择所有技能，并能够使用复选框来添加它们.在视图中，我这样做是这样的:

what I wanna do is allow the person who wants to add a new Course select all the skills from his selected category and be able to add them by using a checkbox. In the view I've done like so:

查看

<%= form_for(@course) do |f| %>
  <% @skills.each do |s| %>
    <%= f.check_box :value => s.id %> <%= s.title %><br />
  <% end %>
<% end %>

不幸的是，这不起作用，并且出现以下错误:

Sadly this isn't working and I get the following error:

undefined method `{:value=>9}' for #<Course:0x00000004ce0208>

您能帮我解决我的问题吗?

could you please help on finding a fix for my issue?

谢谢.

推荐答案

在 Rails 4 中，现在有一个很棒的

In Rails 4 there's now an awesome collection_check_boxes form helper method.

从 Rails API文档 :

<%= form_for @post do |f| %>
  <%= f.collection_check_boxes :author_ids, Author.all, :id, :name_with_initial %>
  <%= f.submit %>
<% end %>

在您的设置中，可能是这样的:

In your setting, it might be something like this:

<%= form_for @course do |f| %>
  <%= f.collection_check_boxes :skill_ids, Skill.all, :id, :name %>
  <%= f.submit %>
<% end %>

关于collection_check_boxes的最酷的事情是可以选择[花一个方块]( http://api.rubyonrails.org/classes/ActionView /Helpers/FormOptionsHelper.html#method-i-collection_check_boxes )，您可以自定义生成的标记(例如，用于样式设置):

The cool thing about collection_check_boxes is that is optionally [takes a block]( http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html#method-i-collection_check_boxes) which let's you customize the generated markup (e.g. for styling purposes):

collection_check_boxes(:post, :author_ids, Author.all, :id, :name_with_initial) do |b|
  b.label(:"data-value" => b.value) { b.check_box + b.text }
end

这篇关于如何在Rails 4中以一种形式添加多个多对多字段?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！