传递行动在的link_to轨道参数3

Question

我已经得到了它是这样一个行动，这发生在一个参数： -

def join_as_student(course) 
     @course = course 
     ......... 

    end 

我有这样的路线： -

resources :courses do 
    member do 
     get :join_as_student 
    end 
    end 

我希望通过单击这样的路线上走这个路线： -

link_to "Join",join_as_student_course_path(:course => @course) 

但是这给了我错误wrong number of arguments (0 for 1) in join_as_student action

如何在link_to中传递此动作的参数？

更新

错误的完整堆栈： -

app/controllers/courses_controller.rb:23:in `join_as_student' 
actionpack (3.1.3) lib/action_controller/metal/implicit_render.rb:4:in `send_action' 
actionpack (3.1.3) lib/abstract_controller/base.rb:167:in `process_action' 
actionpack (3.1.3) lib/action_controller/metal/rendering.rb:10:in `process_action' 
actionpack (3.1.3) lib/abstract_controller/callbacks.rb:18:in `block in process_action' 
activesupport (3.1.3) lib/active_support/callbacks.rb:425:in `_run__26464250__process_action__701751343__callbacks' 
activesupport (3.1.3) lib/active_support/callbacks.rb:386:in `_run_process_action_callbacks' 
activesupport (3.1.3) lib/active_support/callbacks.rb:81:in `run_callbacks' 
actionpack (3.1.3) lib/abstract_controller/callbacks.rb:17:in `process_action' 
actionpack (3.1.3) lib/action_controller/metal/rescue.rb:17:in `process_action' 
actionpack (3.1.3) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action' 
activesupport (3.1.3) lib/active_support/notifications.rb:53:in `block in instrument' 
activesupport (3.1.3) lib/active_support/notifications/instrumenter.rb:21:in `instrument' 
activesupport (3.1.3) lib/active_support/notifications.rb:53:in `instrument' 
actionpack (3.1.3) lib/action_controller/metal/instrumentation.rb:29:in `process_action' 
actionpack (3.1.3) lib/action_controller/metal/params_wrapper.rb:201:in `process_action' 
activerecord (3.1.3) lib/active_record/railties/controller_runtime.rb:18:in `process_action' 
actionpack (3.1.3) lib/abstract_controller/base.rb:121:in `process' 
actionpack (3.1.3) lib/abstract_controller/rendering.rb:45:in `process' 
actionpack (3.1.3) lib/action_controller/metal.rb:193:in `dispatch' 
actionpack (3.1.3) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch' 
actionpack (3.1.3) lib/action_controller/metal.rb:236:in `block in action' 
actionpack (3.1.3) lib/action_dispatch/routing/route_set.rb:65:in `call' 
actionpack (3.1.3) lib/action_dispatch/routing/route_set.rb:65:in `dispatch' 
actionpack (3.1.3) lib/action_dispatch/routing/route_set.rb:29:in `call' 
rack-mount (0.8.3) lib/rack/mount/route_set.rb:152:in `block in call' 
rack-mount (0.8.3) lib/rack/mount/code_generation.rb:96:in `block in recognize' 
rack-mount (0.8.3) lib/rack/mount/code_generation.rb:145:in `optimized_each' 
rack-mount (0.8.3) lib/rack/mount/code_generation.rb:95:in `recognize' 
rack-mount (0.8.3) lib/rack/mount/route_set.rb:141:in `call' 
actionpack (3.1.3) lib/action_dispatch/routing/route_set.rb:532:in `call' 
omniauth (1.0.3) lib/omniauth/strategy.rb:168:in `call!' 
omniauth (1.0.3) lib/omniauth/strategy.rb:148:in `call' 
sass (3.1.15) lib/sass/plugin/rack.rb:54:in `call' 
client_side_validations (3.1.4) lib/client_side_validations/middleware.rb:18:in `call' 
warden (1.1.1) lib/warden/manager.rb:35:in `block in call' 
warden (1.1.1) lib/warden/manager.rb:34:in `catch' 
warden (1.1.1) lib/warden/manager.rb:34:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call' 
rack (1.3.6) lib/rack/etag.rb:23:in `call' 
rack (1.3.6) lib/rack/conditionalget.rb:25:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/head.rb:14:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/params_parser.rb:21:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/flash.rb:247:in `call' 
rack (1.3.6) lib/rack/session/abstract/id.rb:195:in `context' 
rack (1.3.6) lib/rack/session/abstract/id.rb:190:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/cookies.rb:331:in `call' 
activerecord (3.1.3) lib/active_record/query_cache.rb:64:in `call' 
activerecord (3.1.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:477:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call' 
activesupport (3.1.3) lib/active_support/callbacks.rb:392:in `_run_call_callbacks' 
activesupport (3.1.3) lib/active_support/callbacks.rb:81:in `run_callbacks' 
actionpack (3.1.3) lib/action_dispatch/middleware/callbacks.rb:28:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/reloader.rb:68:in `call' 
rack (1.3.6) lib/rack/sendfile.rb:101:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/remote_ip.rb:48:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/show_exceptions.rb:47:in `call' 
railties (3.1.3) lib/rails/rack/logger.rb:13:in `call' 
rack (1.3.6) lib/rack/methodoverride.rb:24:in `call' 
rack (1.3.6) lib/rack/runtime.rb:17:in `call' 
activesupport (3.1.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call' 
rack (1.3.6) lib/rack/lock.rb:15:in `call' 
actionpack (3.1.3) lib/action_dispatch/middleware/static.rb:53:in `call' 
railties (3.1.3) lib/rails/engine.rb:456:in `call' 
rack (1.3.6) lib/rack/content_length.rb:14:in `call' 
railties (3.1.3) lib/rails/rack/log_tailer.rb:14:in `call' 
rack (1.3.6) lib/rack/handler/webrick.rb:59:in `service' 
/usr/local/ruby/lib/ruby/1.9.1/webrick/httpserver.rb:111:in `service' 
/usr/local/ruby/lib/ruby/1.9.1/webrick/httpserver.rb:70:in `run' 
/usr/local/ruby/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread 

'

感谢

Answer 1

对不起，我错过了。你不能通过params来采取行动。使用

link_to "Join",join_as_student_course_path(@course) 

和

def join_as_student 
    @course = Course.find params[:id] 
    ......... 

end 

Answer 2

尝试

link_to "Join",join_as_student_course_path(@course)