Rubyonrails rails respond_to format.js API

发布于11月25日

我是一个经验丰富的java和C++开发人员，我正在try 了解Rails是如何工作的.

我得到以下代码:

respond_to do |format|
      if @line_item.save
        format.html { redirect_to store_url }
        format.js { render :json => @line_item, :mime_type => Mime::Type.lookup('application/json'), 
                :callback => 'javascriptFunction' }

我一直在搜索api，该api定义了我可以在format.js {}中传递的内容，但我找不到..

首先:什么样的语句是format.js，这是一个变量吗？

最重要的是:我可以将哪些属性传递到格式中.js{}？你能通过直连吗？我找了http://api.rubyonrails.org/多个

推荐答案

respond_to do |format|
  format.js # actually means: if the client ask for js -> return file.js
end

js here specifies a mime-type that the controller method would send back as a response;
Default Rails mime-types.
If you try also with format.yaml:

respond_to do |format|
  format.js
  format.yaml
end

这意味着您的控制器将根据客户端的请求返回yml或js；

{} in terms of ruby is a block; If you don't specify any rails will try to render a default file from app/views/[contoller name]/[controller method name].[html/js/...]

# app/controllers/some_controller.rb
def hello
  respond_to do |format|
    format.js
  end
end

将寻找/app/views/some/hello.js.erb；//至少在Rails 2.3版中.

如果确实指定了块:

respond_to do |format|
    # that will mean to send a javascript code to client-side;
    format.js { render             
        # raw javascript to be executed on client-side
        "alert('Hello Rails');", 
        # send HTTP response code on header
        :status => 404, # page not found
        # load /app/views/your-controller/different_action.js.erb
        :action => "different_action",
        # send json file with @line_item variable as json
        :json => @line_item,
        :file => filename,
        :text => "OK",
        # the :location option to set the HTTP Location header
        :location => path_to_controller_method_url(argument)
      }

  end