Ruby How to convert between uppercase and lowercase


This time, we will do a method to convert a character string from uppercase to lowercase in Ruby!

Method used this time -Convert uppercase to lowercase with downcase -Convert lowercase letters to uppercase with upcase ・ Convert between lowercase letters and uppercase letters with swapcase ・ Convert the first lowercase letter to uppercase with capitalize

downcase method

The downcase method is a method used when you want to convert uppercase letters contained in a character string to lowercase letters.

str = "Hello World"
puts str.downcase

[Output result]

hello world

upcase The upcase method is a method used when you want to convert uppercase letters contained in a character string to lowercase letters.

str = "Hello World"
puts str.upcase

[Output result]


swapcase The swapcase method is a method that swaps uppercase and lowercase letters in a character string.

str = "Hello World"
puts str.swapcase

[Output result]


capitalize capitalizeh is a method that converts the first lowercase letter to uppercase

str = "hello world"
puts str.capitalize

[Output result]

Hello World

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