attr_reader :var1
end
class Obj2
def initialize(var2)
@var2 = var2
end
def to_json(*a)
{
"json_class" => self.class,
"data" => {"var2" => @var2}
}.to_json(*a)
end
def self.json_create(json_str)
new(json_str["data"]["var2"])
end
attr_reader :var2
end
class Obj
def initialize(obj1, obj2)
@obj1 = obj1
@obj2 = obj2
end
def to_json(*a)
{
"json_class" => self.class,
"data" => {"obj1" => @obj1.to_json, "obj2" => @obj2.to_json}
}.to_json(*a)
end
def self.json_create(json_str)
new(json_str["data"]["obj1"], json_str["data"]["obj2"])
end
def to_s
"Hi, i am obj"
end
attr_reader :obj1, :obj2
end
obj1 = Obj1.new("i am obj1")
obj2 = Obj2.new("i am obj2")
obj = Obj.new(obj1,obj2)
obj_json_str = obj.to_json
puts "JSON string of obj = #{obj_json_str}"
obj_1 = JSON.parse(obj_json_str)
puts "obj_1 from json string , obj1.class = #{obj_1.obj1.class}, obj2.class = #{obj_1.obj2.class}"
上面代码中，嵌套对象我们惯性思维，是先将对象自己转换为JSON string：
"data" => {"obj1" => @obj1.to_json, "obj2" => @obj2.to_json}
上面代码输出：
JSON string of obj = {"json_class":"Obj","data":{"obj1":"{"json_class":"Obj1","data":{"var1":"i am obj1"}}","obj2":"{"json_class":"Obj2","data":{"var2":"i am obj2"}}"}}
obj_1 from json string , obj1.class = String, obj2.class = String
我们注意到，被嵌套的对象转换为JSON string后，多了一个反斜杠 ：
JSON string of obj = {"json_class":"Obj","data":{"obj1":"{"json_class":"Obj1","data":{"var1":"i am obj1"}}","obj2":"{"json_class":"Obj2","data":{"var2":"i am obj2"}}"}}
