Javascript Rails 4：将局部变量从包含帮助器的表单_的部分传递到js.erb文件

如何将局部变量从form_for helper传递到js文件

我有一个名为_subscribe.html.erb的文件

<%= form_for @subscription, :url => {:controller => "subscriptions", :action => "create"} do |f| %>
  <div><%= hidden_field_tag :group_id, group.id %></div>
  <%= f.submit "Subscribe", class: "btn btn-primary subscribe_btn" %>
<% end %>

这是我的订阅控制器创建操作：

def create
    @subscription = current_user.subscriptions.create(:group_id => params[:group_id])
    @subscription.save
      respond_to do |format|
      format.html { redirect_to groups_path, flash[:success] = "You have successfully subscribed to this group" }
      format.js  
    end
  end

def create
    @group = Group.find(params[:group_id])
    @subscription = current_user.subscriptions.create(:group_id => @group.id)
    @subscription.save
    respond_to do |format|
      format.html { redirect_to groups_path }
      format.js 
    end
  end

但是现在我得到了这个错误：

ActionView::Template::Error (undefined local variable or method `group' for #<#<Class:0x007fe7ecfd4950>:0x007fe7ecfde7e8>):
    1: $("#new_subscription").html("<%= escape_javascript(render('subscriptions/unsubscribe', locals: { group: group } )) %>")
  app/views/subscriptions/create.js.erb:1:in `_app_views_subscriptions_create_js_erb__3184685282411376061_70317032458920'
  app/controllers/subscriptions_controller.rb:8:in `create'

摧毁行动：

def destroy
    @group = Group.find(params[:id])
    @subscription = current_user.subscriptions.find_by(group_id: @group.id)
    @subscription.destroy
    respond_to do |format|
      format.html { redirect_to groups_path }
      format.js
    end
   end

&create.js.erb

$("#subscribe_button").html("<%= escape_javascript(render('subscriptions/unsubscribe', locals: { group: @group } )) %>")

&destory.js.erb

$("#unsubscribe_button").html("<%= escape_javascript(render('subscriptions/subscribe', locals: { group: @group } )) %>")

我仍然在日志中看到以下错误：

Started POST "/subscriptions" for 127.0.0.1 at 2014-11-20 22:23:39 +0000
Processing by SubscriptionsController#create as JS
  Parameters: {"utf8"=>"✓", "group_id"=>"1", "commit"=>"Subscribe"}
  User Load (0.9ms)  SELECT "users".* FROM "users" WHERE "users"."remember_token" = 'b0afd34150d0c021a1e4d0dfa357107a2aa59f00' LIMIT 1
  Group Load (0.4ms)  SELECT "groups".* FROM "groups" WHERE "groups"."id" = $1 LIMIT 1  [["id", "1"]]
   (0.2ms)  BEGIN
  Subscription Exists (0.6ms)  SELECT 1 AS one FROM "subscriptions" WHERE ("subscriptions"."group_id" = 1 AND "subscriptions"."user_id" = 2) LIMIT 1
  SQL (0.6ms)  INSERT INTO "subscriptions" ("created_at", "group_id", "role", "updated_at", "user_id") VALUES ($1, $2, $3, $4, $5) RETURNING "id"  [["created_at", Thu, 20 Nov 2014 22:23:39 UTC +00:00], ["group_id", 1], ["role", "pending"], ["updated_at", Thu, 20 Nov 2014 22:23:39 UTC +00:00], ["user_id", 2]]
   (0.4ms)  COMMIT
   (0.1ms)  BEGIN
  Subscription Exists (0.7ms)  SELECT 1 AS one FROM "subscriptions" WHERE ("subscriptions"."group_id" = 1 AND "subscriptions"."id" != 96 AND "subscriptions"."user_id" = 2) LIMIT 1
   (0.2ms)  COMMIT
  Rendered subscriptions/_unsubscribe.html.erb (100.3ms)
  Rendered subscriptions/create.js.erb (101.7ms)
Completed 500 Internal Server Error in 120ms

ActionView::Template::Error (undefined local variable or method `group' for #<#<Class:0x007fdc05a244a8>:0x007fdc0545b350>):
    1: <%= debug group %>
    2: <div id="unsubscribe_button"> 
    3: <%= button_to "Unsubscribe", subscription_path(group), :remote => true, :method => 'delete', class:  "btn subscribe_btn" %>
    4: </div>
  app/views/subscriptions/_unsubscribe.html.erb:1:in `_app_views_subscriptions__unsubscribe_html_erb__4479900334468069300_70291478478720'
  app/views/subscriptions/create.js.erb:1:in `_app_views_subscriptions_create_js_erb__1667797080065562395_70291478425360'
  app/controllers/subscriptions_controller.rb:8:in `create'

---

您可以清楚地看到@group是在create操作中设置的，并且正在成功地创建订阅，但是js.erb文件中没有设置局部变量

你没有。当前请求结束时，即呈现表单时，执行结束。在提交表单并启动新请求之前，不会调用.js.erb视图模板

---

您必须创建一个实例变量，例如@group=however\u在控制器的create操作中获取\u组，使其对.js.erb视图可见，并引用如下：locals:{group:@group}

问题是，当您在create操作中时，您没有在上一操作中设置的变量

因此，您需要再次设置@group实例变量，然后在create.js.erb模板中使用它

def创建 @group=group.findparams[：group\u id] @subscription=current\u user.subscriptions.create:group\u id=>@group.id @订阅。保存 回应待办事项|格式| format.html{redirect_to groups_path，flash[：success]=您已成功订阅此组} format.js 终止 终止 $new_subscription.html

---

局部变量：{group:@group}是否使组局部变量在传递给它的部分中可用？你的建议对我不起作用？是的。不过，当你们通过@group时，你们必须确保它存在，否则你们的部分中的group将为零。我想我已经找到了答案，但今天又回到了这个问题，我仍然遇到了一个问题，js文件中没有传递局部变量。我已经更新了上面的问题，添加了订阅控制器代码。大多数情况下，在渲染中使用locals键是不必要的，请尝试更改为：$subscribe\u button.html，尽管我不确定这是否会有所不同。在尝试访问组之前，您还可以尝试调试部分中本地\u分配的状态，以查看本地存在的内容。谢谢您的帮助。这仍然会抛出相同的错误。我为上面的问题添加了更多代码。@group变量是在create操作中设置的，但不是在create.js.erb文件中设置的，或者至少它没有按照需要作为局部变量传递。如果您看到新错误，则表示group变量或方法未定义，而不是nil。因此，问题可能在于将属性发送到渲染方法的方式。我认为您还需要发送部分密钥，比如：renderpartial:'subscriptions/unsubscribe'，locals:{group:@group}。问题在于js代码中的密钥。看看上面的答案。。。谢谢你的时间和帮助。

Started POST "/subscriptions" for 127.0.0.1 at 2014-11-20 22:23:39 +0000
Processing by SubscriptionsController#create as JS
  Parameters: {"utf8"=>"✓", "group_id"=>"1", "commit"=>"Subscribe"}
  User Load (0.9ms)  SELECT "users".* FROM "users" WHERE "users"."remember_token" = 'b0afd34150d0c021a1e4d0dfa357107a2aa59f00' LIMIT 1
  Group Load (0.4ms)  SELECT "groups".* FROM "groups" WHERE "groups"."id" = $1 LIMIT 1  [["id", "1"]]
   (0.2ms)  BEGIN
  Subscription Exists (0.6ms)  SELECT 1 AS one FROM "subscriptions" WHERE ("subscriptions"."group_id" = 1 AND "subscriptions"."user_id" = 2) LIMIT 1
  SQL (0.6ms)  INSERT INTO "subscriptions" ("created_at", "group_id", "role", "updated_at", "user_id") VALUES ($1, $2, $3, $4, $5) RETURNING "id"  [["created_at", Thu, 20 Nov 2014 22:23:39 UTC +00:00], ["group_id", 1], ["role", "pending"], ["updated_at", Thu, 20 Nov 2014 22:23:39 UTC +00:00], ["user_id", 2]]
   (0.4ms)  COMMIT
   (0.1ms)  BEGIN
  Subscription Exists (0.7ms)  SELECT 1 AS one FROM "subscriptions" WHERE ("subscriptions"."group_id" = 1 AND "subscriptions"."id" != 96 AND "subscriptions"."user_id" = 2) LIMIT 1
   (0.2ms)  COMMIT
  Rendered subscriptions/_unsubscribe.html.erb (100.3ms)
  Rendered subscriptions/create.js.erb (101.7ms)
Completed 500 Internal Server Error in 120ms

ActionView::Template::Error (undefined local variable or method `group' for #<#<Class:0x007fdc05a244a8>:0x007fdc0545b350>):
    1: <%= debug group %>
    2: <div id="unsubscribe_button"> 
    3: <%= button_to "Unsubscribe", subscription_path(group), :remote => true, :method => 'delete', class:  "btn subscribe_btn" %>
    4: </div>
  app/views/subscriptions/_unsubscribe.html.erb:1:in `_app_views_subscriptions__unsubscribe_html_erb__4479900334468069300_70291478478720'
  app/views/subscriptions/create.js.erb:1:in `_app_views_subscriptions_create_js_erb__1667797080065562395_70291478425360'
  app/controllers/subscriptions_controller.rb:8:in `create'