how to safely replace all whitespaces with underscores with ruby?

Question

This works for any strings that have whitespaces in them

str.downcase.tr!(" ", "_") 

but strings that dont have whitespaces just get deleted

So "New School" would change into "new_school" but "color" would be "", nothing!

Answer 1

with space

str = "New School" str.parameterize.underscore  => "new_school" 

without space

str = "school" str.parameterize.underscore  => "school" 

Edit :- also we can pass '_' as parameter to parameterize.

with space

str = "New School" str.parameterize('_')  => "new_school" 

without space

str = "school" str.parameterize('_')  => "school" 

EDIT:

For Rails 5 and above, use str.parameterize(separator: '_')