Ruby on Rails更新模型，其中单个表单包含多行

Question

I have 2 models Event and Tasks.

Event has many tasks. and task is a nested resource under event so I first create a event and ask a user how many tasks it wants to create in it.

Let say I create a Event and a user wants to create 3 tasks in it. I want to do it in 2 steps and not one

After successful creation of event,now I go to /events/1/tasks/new

here I want to have 3 task name fields and when the user submits it, there should be 3 rows created in Task table against the Event 1

How do I achieve this

So here is the task _form.html.erb

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

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

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

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

Task controller

def new
     @event=Event.find(params[:event_id])
    @event.task_count do
      @choice = @event.tasks.build
    end
    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @task }
    end
  end


  # POST /tasks
  # POST /tasks.json
  def create
    @task = Task.new(params[:task])

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

Answer 1

I think you are making this more complicated by involving the tasks controller. Controllers direct actions in the web application. But by your description you seem to be wanting to have 3 tasks auto created when the event is created (if I'm understanding you correctly). Other than entering the initial names this doesn't really involve the user.

Have them submit the names and when the events controller creates the event it should create the tasks there.

If your nested resource is more complicated it is a job for nested forms. You might benefit from this screencast:

http://railscasts.com/episodes/196-nested-model-form-part-1

Answer 2

First you intilized 3 task aginst one eveent in this way

  def new
   @event=Event.find(params[:event_id])
   3.times{@event.tasks.build}

   respond_to do |format|
    format.html # new.html.erb
    format.json { render json: @task }
   end
  end

Then it will be surely create 3 task against 1 event.or you can help from ryan rails cast for nested forms also