What's the best way to search for a string in a file?

Question

The title speaks for itself really. I only want to know if it exists, not where it is. Is there a one liner to achieve this?

Answer 1

Well it seems eed3si9n has the one liner down, here's the longer solution:

f = File.new("file.txt")
text = f.read
if text =~ /string/ then
#relevant code
end