问题
This is probably a very simple fix but I've been unable to find an answer just yet.
My application has orders and tasks. Orders have many tasks. When a user clicks new task in the show order view, it passes the order.id:
<%= link_to "New Task", new_task_path(:order_id=> @order.id) %>
The url shows:
/tasks/new?order_id=1
I just don't know how to extract this and use it in my form? I have tried:
<%= f.text_field :order_id, :value => @order_id %>
But it's not working.
回答1:
You can do:
<%= f.text_field :order_id, :value => params[:order_id] %>
Alternately, capture the value (with params) in the controller and assign it to @order_id there.
回答2:
You are doing this wrong, which is a big deal in Rails where convention-over-configuration is such an important ideal.
If an order has many tasks, your route should look like this:
/orders/:order_id/tasks/new
And your routes should be configured thusly:
resources :orders do
resources :tasks
end
You should [almost] never find yourself passing around record ids in the query string. In fact, you should almost never find yourself using query strings at all in Rails.
来源：https://stackoverflow.com/questions/6306690/ruby-on-rails-passing-parameter-in-url