Check if file contains string

Question

So I found this question on here, but I\'m having an issue with the output and how to handle it with an if statement. This is what I have, but it\'s always saying that it\'s tru

Answer 1

Enumerable#grep does not return a boolean; it returns an array (how would you have access to the matches without passing a block otherwise?).

If no matches are found it returns an empty array, and [] evaluates to true. You'll need to check the size of the array in the if statement, i.e.:

if File.readlines("testfile.txt").grep(/monitor/).size > 0
  # do something
end

The documentation should be your first resource for questions like this.