-class Hash
- # Returns a JSON string representing the hash.
- #
- # Without any +options+, the returned JSON string will include all
- # the hash keys. For example:
- #
- # { :name => "Konata Izumi", 'age' => 16, 1 => 2 }.to_json
- # # => {"name": "Konata Izumi", "1": 2, "age": 16}
- #
- # The keys in the JSON string are unordered due to the nature of hashes.
- #
- # The <tt>:only</tt> and <tt>:except</tt> options can be used to limit the
- # attributes included, and will accept 1 or more hash keys to include/exclude.
- #
- # { :name => "Konata Izumi", 'age' => 16, 1 => 2 }.to_json(:only => [:name, 'age'])
- # # => {"name": "Konata Izumi", "age": 16}
- #
- # { :name => "Konata Izumi", 'age' => 16, 1 => 2 }.to_json(:except => 1)
- # # => {"name": "Konata Izumi", "age": 16}
- #
- # The +options+ also filter down to any hash values. This is particularly
- # useful for converting hashes containing ActiveRecord objects or any object
- # that responds to options in their <tt>to_json</tt> method. For example:
- #
- # users = User.find(:all)
- # { :users => users, :count => users.size }.to_json(:include => :posts)
- #
- # would pass the <tt>:include => :posts</tt> option to <tt>users</tt>,
- # allowing the posts association in the User model to be converted to JSON
- # as well.
- def to_json(options = {}) #:nodoc:
- hash_keys = self.keys
-
- if except = options[:except]
- hash_keys = hash_keys - Array.wrap(except)
- elsif only = options[:only]
- hash_keys = hash_keys & Array.wrap(only)
- end
-
- result = '{'
- result << hash_keys.map do |key|
- "#{ActiveSupport::JSON.encode(key.to_s)}: #{ActiveSupport::JSON.encode(self[key], options)}"
- end * ', '
- result << '}'
- end
-end