Ruby – Class Methods

A class method is essentially the c# equivalent of a “static method”. A good example would be a “calculator” class, where you have a “class method” called “add” which adds 2 numbers together.

In this situation, it makes no sense to create a “calculator” object and then use the “add” method. Instead we would want to use the “add” method directly.

To define a class-method, we once again make use of the “self” keyword:

class Calculator 
  def self.add(first_number,second_number)
    first_number + second_number             # remember the output is automatically returned. 
                                             # You don't need to explicitly state a return statement
											 
  end
  
end

result = Calculator.add(2,5)     # here we are just drilling down to the class 
                                 # that has the "add" method, similar to c#.

puts "The sum of 2 and 5 is: #{result}"