| Module | ERB::Util | 
| In: | lib/action_view/erb/util.rb | 
| HTML_ESCAPE | = | { '&' => '&', '>' => '>', '<' => '<', '"' => '"' } | 
| JSON_ESCAPE | = | { '&' => '\u0026', '>' => '\u003E', '<' => '\u003C' } | 
A utility method for escaping HTML tag characters. This method is also aliased as h.
In your ERb templates, use this method to escape any unsafe content. For example:
<%=h @person.name %>
  puts html_escape("is a > 0 & a < 10?")
  # => is a > 0 & a < 10?
        A utility method for escaping HTML entities in JSON strings. This method is also aliased as j.
In your ERb templates, use this method to escape any HTML entities:
<%=j @person.to_json %>
  puts json_escape("is a > 0 & a < 10?")
  # => is a \u003E 0 \u0026 a \u003C 10?