How to code "press key to continue"

Question

I am trying to implement a simple "Press any key to continue". I print this message to the console, and I want to erase it after a key is pressed.

Following "Writing over previously output lines in the command prompt with ruby", I tried this piece of code:

def continue
  print "Press any key to continue\r"
  gets
end

puts "An awesome story begins..."
continue
puts "And ends after 2 lines"

However, the \r trick doesn't work and the next puts won't erase the sentence. Is it because of a different function context? The gets spawns a newline? Or because I'm on Windows OS?

Answer 1

You can use STDIN from the IO class, rather than gets.

require 'io/console'                                                                                                       
def continue_story                                                                                                               
  print "press any key"                                                                                                    
  STDIN.getch                                                                                                              
  print "            \r" # extra space to overwrite in case next sentence is short                                                                                                              
end                                                                                                                        

puts "An awesome story begins..."                                                                                          
continue_story                                                                                                                   
puts "And ends after 2 lines"    

This has the added bonus that it only requires one character to be entered (getch - get character) allowing the 'press any key' to work without a return or enter.