Learn Rails 6: Accelerated Web Development with Ruby on Rails

Appendix: Validations

Validation	Purpose
acceptance	Validates that a check box, for instance, on the user interface was checked when a form was submitted. It accepts various options such as accept, and so forth.
confirmation	Validates that two text fields, for instance, should receive exactly the same content.
exclusion	Validates that a value is not included in a given array. It accepts various options such as in, and so forth.
format	Validates that a value matches with a given regular expression. It accepts various options such as with, and so forth.
inclusion	Validates that a value is among a given array. It accepts various options such as in, and so forth.
length	Validates the length of a value, for example, of a given password that should be at ...