命名路由
path是相對路徑
url是絕對路徑
model為復數的會對應到action=>index, 為單數時需要傳遞id參數并對應到action=>show
如對于user而言:
users_url # => http://localhost:3000/users
users_path # => /users
user_path(1) # => /users/1
user_url(1) # => http://localhost:3000/users/1
區別_url與_path