ruby - How to test if parameters exist in rails

Question

I'm using an IF statement in Ruby on Rails to try and test if request parameters are set. Regardless of whether or not both parameters are set, the first part of the following if block gets triggered. How can I make this part ONLY get triggered if both params[:one] and params[:two] is set?

if (defined? params[:one]) && (defined? params[:two])
 ... do something ...
elsif (defined? params[:one])
 ... do something ...
end

Answer 1

You want has_key?:

if(params.has_key?(:one) && params.has_key?(:two))

Just checking if(params[:one]) will get fooled by a "there but nil" and "there but false" value and you're asking about existence. You might need to differentiate:

• Not there at all.
• There but nil.
• There but false.
• There but an empty string.

as well. Hard to say without more details of your precise situation.