Question

(as a follow up to this question: In Jquery AND Rails, how to get visible character count of a string?)

Let’s say you have a string with embedded links and tags like so:

 This string has <a href="http://www.google.com">some links</a> inside it.

Then the visible string to a user is:

 This string has some links inside it.

The full string has 73 characters and the visible just 37 characters.

Let’s say I now want to write a rails validation (custom validation) that checks the visible length of the string. ie:

 validate :string_visible_length

 def string_visible_length
      #some code that verifies the character length of a field named :field_name
 end

Any ideas how to accomplish this? I would need to strip the html tags and then check the character length..

Answer 1

I think you could use the strip links method in your validation.

Make helpers available in your model file:

  include ActionView::Helpers

Here’s the validation:

  validate :string_visible_length

private

  def string_visible_length
    visible_string = strip_links(self.column_name) # where column_name is the field you need validated
    errors.add(:base, 'Visible string is too long') if visible_string.length > 20 # 20 is whatever length you need
  end