Params Includes Submission Button Info

When a form is submitted for a Rails app, the respective controller action will have access to a variety of information in the params hash. Included is an entry with the name and value of the button that submitted the form. By default, Rails will give the name commit to a submission button.

<%= f.submit %>
# results in:
<input type="submit" name="commit" value="Submit">Submit</input>

The corresponding create action will have parameters that include that submission button's info:

# in create action
> params['commit']
=> 'Submit'

This is useful when you have multiple buttons that submit the same form, but should have slightly different results in the corresponding action. Differentiating becomes easy when you can easily check which was used to submit the form. No javascript required.