Rails: How to validate format only if value is present?

by

You can use the option allow_blank: true to skip the validation when the attribute is blank/empty/nil.

https://guides.rubyonrails.org/active_record_validations.html#allow-blank

Related Contents:

  1. Validate uniqueness of multiple columns
  2. Ruby on Rails Callback, what is difference between :before_save and :before_create?
  3. Rails 3: “field-with-errors” wrapper changes the page appearance. How to avoid this?
  4. Rails – Validate Presence Of Association?
  5. validation custom message for rails 3
  6. What is the order of ActiveRecord callbacks and validations?
  7. Controlling the order of rails validations
  8. Rails DB Migration – How To Drop a Table?
  9. Add a CSS class to
  10. Repairing Postgresql after upgrading to OSX 10.7 Lion
  11. do..end vs curly braces for blocks in Ruby
  12. How to add 10 days to current time in Rails
  13. Rails: How to change the text on the submit button in a Rails Form
  14. How to delete migration files in Rails 3
  15. Check if record exists from controller in Rails
  16. How do I prepare test database(s) for Rails rspec tests without running rake spec?
  17. How to check if a number is included in a range (in one statement)?
  18. How to run rails s -p80 on 80 port?
  19. Setting Devise Login to be root page
  20. before_filter with parameters
  21. How to get a single column’s values into an array
  22. how to safely replace all whitespaces with underscores with ruby?
  23. Where to put Ruby helper methods for Rails controllers?
  24. Parsing string to add to URL-encoded URL
  25. Alias for column names in Rails
  26. Why is my custom rake task in lib/tasks not discovered in Rails 3?
  27. How to display a Rails flash notice upon redirect?
  28. Rails 3 / Form without Model: How do I create a form that is not tied to a model?
  29. Ruby syntax: break out from ‘each.. do..’ block
  30. Find the newest record in Rails 3
  31. Rails order by results count of has_many association
  32. Role does not exist and unable to create database when using PostgreSQL
  33. Rails naming convention for join table
  34. rails, simple_form, how to set selected index of a collection when page loaded?
  35. Why does false invalidate validates_presence_of?
  36. How to tell which format a controller has resolved to render
  37. Sending mail with Rails 3 in development environment
  38. How to update a single attribute without touching the updated_at attribute?
  39. Rails – Mail, getting the body as Plain Text
  40. rails get app root/base url
  41. Rails: Per-environment initializers?
  42. association named not found perhaps misspelled issue in rails association
  43. Shortcut for plucking two attributes from an ActiveRecord object?
  44. Filter to execute before render but after controller?
  45. redirect to index rather than show after save
  46. How would you create a notification system like on SO or Facebook in RoR?
  47. How to validate the date such that it is after today in Rails?
  48. Iterating between two DateTimes, with a one hour step
  49. How can I detect if my code is running in the console in Rails 3?
  50. Rails 3 SSL routing redirects from https to http

Leave a Comment