How to check if a param is true or false?

Question

This is really racking my brain, but maybe I'm trying to hard.

I'm passing a param via a URL (example.com?debug=true)

So I basically want to say:

if params[:debug] == true  do xyz else  do abc end 

But for whatever reason that if statement just isn't doing like it seems like it should.

Is there a better way to do that if/else statement based on a param being true or false?

The debug param will either have a value of true, no value, or a value of false (as far as the URL goes).

Answer 1

params come in as strings, so you need to compare against "true", not true.

Answer 2

You could use ActiveRecord's method of checking truthful values if you don't want to reinvent the wheel (this is what is used when passing params inside an ActiveRecord object

Rails 3-4.1

if ActiveRecord::ConnectionAdapters::Column.value_to_boolean(params[:debug])     do xyz else     do abc 

Rails 4.2.0

ActiveRecord::Type::Boolean.new.type_cast_from_database(params[:debug]) 

Rails 5

ActiveModel::Type::Boolean.new.cast(params[:debug]) 

Might be worth wrapping in a helper but never the less it's quite flexible:

rails c Loading development environment (Rails 3.2.6) 1.9.3p194 :001 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean '1'  => true  1.9.3p194 :002 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean '0'  => false  1.9.3p194 :003 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 1  => true  1.9.3p194 :004 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean true  => true  1.9.3p194 :005 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'true'  => true  1.9.3p194 :006 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'on'  => true  1.9.3p194 :007 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean 'off' 

Custom extension

Some people frown on extending core classes but this does fit with the DRY principle.

# config/initializer/boolean.rb class Boolean   def self.parse(value)     ActiveRecord::ConnectionAdapters::Column.value_to_boolean(value)   end end 

Then used like

if Boolean.parse(params[:debug])   then xyz