Type:
Module
Constants:
NaN : 0.0/0
Infinity : 1.0/0
MinusInfinity : -Infinity
UnparserError : GeneratorError

This exception is raised if a generator or unparser error occurs.

JSON_LOADED : true unless defined?(::JSON::JSON_LOADED)
VERSION : '1.7.7'

JSON version

VERSION_ARRAY : VERSION.split(/\./).map { |x| x.to_i }
VERSION_MAJOR : VERSION_ARRAY[0]
VERSION_MINOR : VERSION_ARRAY[1]
VERSION_BUILD : VERSION_ARRAY[2]

JavaScript Object Notation (JSON)

JSON is a lightweight data-interchange format. It is easy for us humans to read and write. Plus, equally simple for machines to generate or parse. JSON is completely language agnostic, making it the ideal interchange format.

Built on two universally available structures:

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1. A collection of name/value pairs. Often referred to as an _object_, hash table, record, struct, keyed list, or associative array.
2. An ordered list of values. More commonly called an _array_, vector, sequence or list.

To read more about JSON visit: json.org

Parsing JSON

To parse a JSON string received by another application or generated within your existing application:

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require 'json'
 
my_hash = JSON.parse('{"hello": "goodbye"}')
puts my_hash["hello"] => "goodbye"

Notice the extra quotes '' around the hash notation. Ruby expects the argument to be a string and can't convert objects like a hash or array.

Ruby converts your string into a hash

Generating JSON

Creating a JSON string for communication or serialization is just as simple.

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require 'json'
 
my_hash = {:hello => "goodbye"}
puts JSON.generate(my_hash) => "{\"hello\":\"goodbye\"}"

Or an alternative way:

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require 'json'
puts {:hello => "goodbye"}.to_json => "{\"hello\":\"goodbye\"}"

JSON.generate only allows objects or arrays to be converted to JSON syntax. to_json, however, accepts many Ruby classes even though it acts only as a method for serialization:

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require 'json'
 
1.to_json => "1"
restore
  • References/Ruby on Rails/Ruby/Classes/JSON

restore(source, proc = nil, options = {}) Class Public methods Alias for:

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as_json
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::GenericObject

as_json(*) Instance Public methods

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fast_generate
  • References/Ruby on Rails/Ruby/Classes/JSON

fast_generate(obj, opts = nil) Instance Public methods Generate a

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array_nl
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::State

array_nl() Instance Public methods This string is put at the end of a line

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buffer_initial_length=
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::State

buffer_initial_length=(length) Instance Public methods This sets the initial

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included
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::GeneratorMethods/JSON::Ext::Generator::GeneratorMethods::String

String.included(modul) Class Public methods Extends modul with the

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to_json
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::GeneratorMethods/JSON::Ext::Generator::GeneratorMethods::Fixnum

to_json(*) Instance Public methods Returns a

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json_creatable?
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::GenericObject

json_creatable?() Class Public methods

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indent=
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::State

indent=(indent) Instance Public methods This string is used to indent levels

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to_json
  • References/Ruby on Rails/Ruby/Classes/JSON/JSON::Ext/JSON::Ext::Generator/JSON::Ext::Generator::GeneratorMethods/JSON::Ext::Generator::GeneratorMethods::NilClass

to_json(*) Instance Public methods Returns a

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