Validate that a value is in a certain range, e.g. 1 <= val <=2

Question

I want to validate a number :value to be within 1 or 2

validates :value, :format => { :with => /1|2/, :message => \"Select number..\" }


        

Answer 1

if you want it to be a number within 1 and 2 ( 1.5, 1.6839749, etc ) do

validates_numericality_of :value, :greater_than_or_equal_to => 1, :less_than_or_equal_to => 2, :message => "blah"

may not be what you are looking for but is worth noting,

Answer 2

You're looking for validates_inclusion_of:

validates_inclusion_of :value, :in => [1, 2],
  :message => "Select one of %{value}"

You can also use the (fairly new) shothand form and a Range instead of an Array:

validates :value, :inclusion => { :in => 1..2 }

Answer 3

If you use inclusion error messages are not good:

["Value is not included in the list"]

Use

validates :value, presence: true, numericality: { greater_than_or_equal_to: 1, less_than_or_equal_to: 10 }

For better error messages, like:

["Value must be less than or equal to 2"]

Answer 4

validates :value, :inclusion => {:in => [1,2]}

See http://apidock.com/rails/ActiveModel/Validations/HelperMethods/validates_inclusion_of