ruby check if string is an integer code example

Example 1: ruby is int

1.is_a? Integer
=> true
"[email protected]".is_a? Integer
=> false
nil.is_a? Integer
=> false

Example 2: ruby test is number

12.is_a? Numeric

Example 3: ruby check if string is integer

class String
  def numeric?
    Float(self) != nil rescue false
  end
end
"Hello World!".numeric?