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rubystringuppercaselowercase

How to convert a string to lower or upper case in Ruby

How do I take a string and convert it to lower or upper case in Ruby?

Solution

  • Ruby has a few methods for changing the case of strings. To convert to lowercase, use downcase:

    "hello James!".downcase    #=> "hello james!"

    Similarly, upcase capitalizes every letter and capitalize capitalizes the first letter of the string but lowercases the rest:

    "hello James!".upcase      #=> "HELLO JAMES!"
"hello James!".capitalize  #=> "Hello james!"
"hello James!".titleize    #=> "Hello James!" (Rails/ActiveSupport only)

    If you want to modify a string in place, you can add an exclamation point to any of those methods:

    string = "hello James!"
string.downcase!
string   #=> "hello james!"

    Refer to the documentation for String for more information.