json

JSON.rb

#JSON is frequently used to exchange data between JavaScript running in browsers and server-based applications

#把hash或array的数据结构转换成字符，并把字符写入文件
>> require 'json'
=> true
>> data = { :name => 'louis', :address => ['Suzhou', 'China'], :age => 30}
=> {:address=>["Suzhou", "China"], :age=>30, :name=>"louis"}
>> serialized = data.to_json
=> "{"address":["Suzhou","China"],"age":30,"name":"louis"}"
>> File.open('data.txt', 'w') do |f|
?> f.puts serialized
>> end

#从文件中读取字符化的数据，并转换为数据结构
require 'json'
serialized = File.read("data.txt")
data = JSON.parse(serialized)
=> {"name"=>"dave", "address"=>["tx", "usa"], "age"=>17}

#通过j或jj把其参数转换为JSON格式，并打印到STDOUT
>> data = { :name => 'louis', :address => ['Suzhou', 'China'], :age => 30}
>> jj data
{
  "address": [
    "Suzhou",
    "China"
  ],
  "age": 30,
  "name": "louis"
}

>> j data
{"address":["Suzhou","China"],"age":30,"name":"louis"}