Say you want to include a field in a form that says which link your user clicked to get to that form. Did they come from your homepage? From a blog entry?
Who knows? You do. At least now you do.
Here's an example. On a real estate site I was making, I wanted people to click a "buy a house" button or a "buy an apartment" button. Either button would send them to the same survey, but I wanted the survey to record how they got there.
For the two buttons, I added a boolean value, that got passed to the survey in the url.
The links were:
<%= link_to new_quick_path(house: true) do %>House<% end %>
<%= link_to new_quick_path(house: false) do %>Apartment<% end %>.
This translated into a url like this bad boy:
Then in the form, I included a hidden field which grabbed this parameter:
<%= f.hidden_field :house, value: params[:house] %>
Bippity boppity boop.