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Ruby Building Web Apps with Sinatra ERB Templates URL Parameters

Posted by David Greenstein
David Greenstein
6,734 Points

What is the params[:title] connected to?

I understand the concept of storing the information provided in the submit box as an instance variable but where do we set params to take in :title.

Later on in the videos we use name in the erb file for title and content keys in the hashes. We do not do that in the show.erb file so I was wondering how params knows to accept a key called title.

1 Answer

Ari Misha
Ari Misha
19,323 Points
Ari Misha
Ari Misha
19,323 Points

Hiya there! Im pretty sure you're already familiar by now with monkey patching and how Ruby creates methods on the fly and OOPs concept in Ruby. Whenever you create a class , you also define initialize method either by overriding or ruby does it for you behind the scenes. Any attribute starting with @ symbol represents the instance variables. And instance variables can be accessed outside the class as well by any object.

So say a user inputs something in the url as title and you wanna capture it, right? It can be captured with params object. Its a global object which has all kinds of information stored in it. Hence, title key can be accessed with params[:title]. Moreover, if you assign the captured url params to an instance variable in the controller class, it'll be always available to you in the views.

~ Ari