【Ruby】【YAML】

require "YAML"

var = YAML.load(File.open('b.yml'))

#哈希
puts var.class                                      #Hash
print var ,"\n"                               #{"data"=>{"list"=>["Item1", "Item2", "Item3"], "hash"=>{"key1"=>"value1", "key2"=>"value2", "key3"=>"value3"}}}

print var["data"].class,"\n"                  #Hash
print var["data"],"\n"                        #{"list"=>["Item1", "Item2", "Item3"], "hash"=>{"key1"=>"value1", "key2"=>"value2", "key3"=>"value3"}}

print var["data"]["hash"].class,"\n"          #Hash
print var["data"]["hash"],"\n"                #{"key1"=>"value1", "key2"=>"value2", "key3"=>"value3"}

#列表
print var["data"]["list"].class                     #Array
print var["data"]["list"] ,"\n"               #Array["Item1","Item2","Item3"]

#字符串和其他类型
=begin
YAML会自动判断类型。一般性的文字都会被解析成字符串。在有可能发生歧义的情况下，可为字符串加上单引号或者双引号
=end

print var["data"]["str"].class,"\n"           #Hash
print var["data"]["str"],"\n"                 #1=>1.0, 1.0=>"1.0", "1.0"=>#<Date: 2006-01-01 ((2453737j,0s,0n),+0s,2299161j)>}

#字符串块
=begin
用| 表示保留换行符
用>表示删除换行符
=end
print var["data"]["strBone"].class,"\n"
print var["data"]["strBone"]
print var["data"]["strBone2"].class,"\n"
print var["data"]["strBone2"]
=begin
String
this is line1.
this is line2.
this is line3.
String
Hello, world.
=end

# 完整的例子  对于重复出现的项目，可以用&进行定义，然后用*进行引用
var2  = YAML.load(File.open("abc.yml"))

print var2.class,"\n"      #Hash
print var2
=begin
{
  "items"=>[
    {"price"=>1.47, "quantity"=>4, "part_no"=>"A4786", "descrip"=>"Water Bucket (Filled)"},
    {"price"=>100.27, "quantity"=>1, "part_no"=>"E1628", "descrip"=>"High Heeled /"Ruby/" Slippers"}
  ],
  "bill-to"=>{"city"=>"East Westville", "street"=>"123 Tornado Alley/nSuite 16/n", "state"=>"KA"},
  "specialDelivery"=>"Follow the Yellow Brick Road to the Emerald City. Pay no attention to the  man behind the curtain.",
  "date"=>#<Date: 4908637/2,0,2299161>,
  "ship-to"=>{"city"=>"East Westville", "street"=>"123 Tornado Alley/nSuite 16/n", "state"=>"KA"},
  "customer"=>{"given"=>"Dorothy", "family"=>"Gale"},
  "logEvent"=>"Purchase Invoice"
}
=end

【b.yml】

data:
 list:
  - Item1
  - Item2
  - Item3

 hash:
  key1: value1
  key2: value2
  key3: value3

 str:
  1: 1.0
  1.0: "1.0"
  "1.0": 2006-01-01

 strBone:
  |
   this is line1.
   this is line2.
   this is line3.

 strBone2:
  >
   Hello,
   world.

【abc.yml】

logEvent: Purchase Invoice
date: 2018-07-12
customer:
 given: Dorothy
 family: Gale

bill-to: &id001
 street: |
        123 Tomado Alley
        Suite 16
 city: East Westvile
 state: KA

ship-to: *id001

items:
  - part_no: A476
    descrip: Water Bucket(Filled)
    price: 1.47
    quantity: 4

  - part_no: E1628
    descrip: High Heeled "Ruby" Slippers
    price: 100.27
    quantity: 1

specialDelivery: >
 Follow the yellow Brick
 Road to the Emeraid City.
 Pay no attention to the
 man being the curtain.