Ruby on rails rails 4带参数的路由

这是我的路线设置

resources :messages do
  collection do
    get 'message'
  end      
end

它工作正常，但我想添加一个参数到这个路由

resources :messages do
  collection do
    get 'message/:username'
  end      
end

我在运行

rake routes

rake aborted!
missing :action
/home/li/data/git/projectname/config/routes.rb:5:in `block (4 levels) in <top (required)>'
/home/li/data/git/projectname/config/routes.rb:4:in `block (3 levels) in <top (required)>'
/home/li/data/git/projectname/config/routes.rb:3:in `block (2 levels) in <top (required)>'
/home/li/data/git/projectname/config/routes.rb:2:in `block in <top (required)>'
/home/li/data/git/projectname/config/routes.rb:1:in `<top (required)>'
/home/li/data/git/projectname/config/environment.rb:5:in `<top (required)>'
Tasks: TOP => routes => environment
(See full trace by running task with --trace)

rake中止！
缺失：行动
/home/li/data/git/projectname/config/routes.rb:5:in'block（4层）in'
/home/li/data/git/projectname/config/routes.rb:4:in'block（3层）in'
/home/li/data/git/projectname/config/routes.rb:3:in'block（2层）in'
/home/li/data/git/projectname/config/routes.rb:2:in'block in'
/home/li/data/git/projectname/config/routes.rb:1:in`'
/home/li/data/git/projectname/config/environment.rb:5:in`'
任务：TOP=>routes=>environment
（通过使用--trace运行任务查看完整跟踪）

向该路由添加参数的正确方法是什么？

应该是

resources :messages do
  collection do
    get 'message/:username' => :message
  end      
end

如果要使用

消息\u消息\u url

和

消息\u消息\u路径

，请使用带有

as:

选项的命名路由：

resources :messages do
  collection do
    get 'message/:username' => :message, as: 'messages_message'
  end      
end

---

为什么

get'message/:username'=>'message'

不起作用？@wwli我不确定，我认为

get'message'

是

get'message'=>'message'

的快捷方式，它不能与动态段一起工作。很抱歉再次打扰你，我试图运行

rake-routes

为什么前缀是空的。我试图使用

messages\u messages\u path

我遇到了一个错误

undefined method

messages\u path`这个路由缺少一些设置？