How to search a folder and all of its subfolders for files of a certain type

Question

I am trying to search for all files of a given type in a given folder and copy them to a new folder.

I need to specify a root folder and search through that folder a

Answer 1

Try this:

Dir.glob("#{folder}/**/*.pdf")

which is the same as

Dir["#{folder}/**/*.pdf"]

Where the folder variable is the path to the root folder you want to search through.