去掉.

app/controllers/homework_attach_controller.rb

@@ -42,7 +42,7 @@ class HomeworkAttachController < ApplicationController
     @homework_list = paginateHelper all_homework_list,10
     @direction = direction == 'asc'? 'desc' : 'asc'
     respond_to do |format|
-      format.js.
+      format.js
     end
   end