Module: EAN

Included in:
String
Defined in:
lib/ean/ean.rb,
lib/ean/version.rb

Overview

:nodoc:

Defined Under Namespace

Modules: VERSION

Instance Method Summary collapse

Instance Method Details

#ean? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ean/ean.rb', line 37

def ean?
  numbers = self.to_s.gsub(/[\D]+/, "").split(//)

  checksum = 0
  case numbers.length
  when 8
    0.upto(numbers.length-2) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  when 12
    0.upto(numbers.length-2) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  when 13
    0.upto(numbers.length-2) do |i| checksum += numbers[i].to_i * (i%2*3 +(i-1)%2) end
  when 14
    0.upto(numbers.length-2) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  else
    return false
  end

  return numbers[-1].to_i == (10 - checksum % 10)%10
end

#generate_check_digit ⇒ Object 



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# File 'lib/ean/ean.rb', line 17

def generate_check_digit
  numbers = self.to_s.gsub(/[\D]+/, "").split(//)

  checksum = 0
  case numbers.length
  when 7
    0.upto(numbers.length-1) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  when 11
    0.upto(numbers.length-1) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  when 12
    0.upto(numbers.length-1) do |i| checksum += numbers[i].to_i * (i%2*3 +(i-1)%2) end
  when 13
    0.upto(numbers.length-1) do |i| checksum += numbers[i].to_i * ((i-1)%2*3 +i%2) end
  else
    0
  end

  return ((10 - checksum % 10)%10).to_s
end

#to_gtin ⇒ Object 



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# File 'lib/ean/ean.rb', line 57

def to_gtin
  numbers = self.to_s.gsub(/[\D]+/, "")
  case numbers.length
  when 8
    '000000'+numbers
  when 12
    '00'+numbers
  when 13
    '0'+numbers
  when 14
    numbers
  else
    '00000000000000'
  end
end