CODEWITHSUNDEEP
ruby
Alexandr Krivosheev
Alexandr Krivosheev

Reputation: 73

How can I disable capitalized input?

How can I prevent user uppercase letters input with

user = get.chomp

if I don`t want use 

user.downcase!

I want user can`t input uppercase letters

Upvotes: 0

Views: 55

Answers (2)

peter
peter

Reputation: 42182

Yes you can do that in the following way, getch takes one character at a time. One caviat: you need to end the string with two returns. Keep in mind that this is only the console, if you want more or fancier control use a simple GUI framework like eg Shoes of use a web-interface.

require 'io/console'

input, user = "", ""
while input != "\n"
  input = STDIN.getch
  if ('a'..'z').include? input
    print input
    user += input 
  end
end
puts "\nuser = #{user}"

Upvotes: 1

tadman
tadman

Reputation: 211560

If you want to verify that it's all downcase the easy way is:

user = gets.chomp

if (user == user.downcase)
  # All downcase
end

You can also use a regular expression:

user = gets.chomp

if (user.match(/\A[a-z]\z/)
  # All downcase
end

That will let you customize which characters are allowed, like if _ is acceptable.

You can't prevent them from typing in upper-case letters unless you do a lot of work with something like Curses to process individual keystrokes and assume control over echoing output. This is a ton of work and I wouldn't recommend it.

Upvotes: 0

Related Questions