Converting a String to Lower or Upper Case

In Ruby, you can easily convert a string to either lower case or upper case using built-in methods.

Converting to Lower Case with downcase

What is downcase?

The downcase method is used to convert a string to lower case. It returns a new string with all characters converted to their lowercase equivalent.

Syntax of downcase

lower_case_string = original_string.downcase

Example

original_string = "Hello, World!"
lower_case_string = original_string.downcase
puts lower_case_string

In this example, the downcase method is applied to the original_string, and the result is printed to the console. The output will be "hello, world!".

Converting to Upper Case with upcase

What is upcase?

The upcase method is used to convert a string to upper case. It returns a new string with all characters converted to their uppercase equivalent.

Syntax of upcase

upper_case_string = original_string.upcase

Example

original_string = "Hello, World!"
upper_case_string = original_string.upcase
puts upper_case_string

In this example, the upcase method is applied to the original_string, and the result is printed to the console. The output will be "HELLO, WORLD!".

Modifying the Original String with downcase! and upcase!

Both downcase and upcase methods have destructive counterparts downcase! and upcase!, which modify the original string in place.

Example

original_string = "Hello, World!"
original_string.downcase!
puts original_string

In this example, the downcase! method is applied to the original_string, modifying it in place. The output will be "hello, world!".

original_string = "Hello, World!"
original_string.upcase!
puts original_string

In this example, the upcase! method is applied to the original_string, modifying it in place. The output will be "HELLO, WORLD!".