One, Jsonjson:javascript object Notation (JavaScript object notation) JSON is the syntax for storing and exchanging textual information 1, JSON Lightweight: Syntax rules JSON syntax is a subset of JavaScript object notation syntax. (1) data in name/value pairs (2) data is separated by commas (3) A curly brace represents an object (4) [] array, can hold multiple objects (5) string using double quotation marks Two, Python type and JSON type conversion 1, the Python data, Convert to JSON format json.dumps (data,sort_keys=true,indent=4,separators= (', ', ': '), Skipkeys=true,ensure_ascii=false) Sort_ The keys default is False. Whether to sort by dictionary (A to Z) output: True (sorted by dictionary) indent: Each value is displayed in front of the empty 4-separators: Using the established character substitution, the function of the parameter is to remove the comma "," and the semicolon ":" After the space Skipkeys: Ignore the wrong data ensure_ascii: The default is true: the display outside the character is \u4e2d\u56fd 2, JSON decoding: Convert the JSON format into Python format json.loads () The JSON object type-----The array type of Python's dict type json------python's list type import jsondata = [{' A ': ' A ', ' B ':(2,4), ' C ': 3.0 , ' d ': None, ' e ': true}]print Datadatajson = Json.dumps (' data,sort_keys=true,separators= (', ', ': '), indent=4,skipkeys= True) Print Datajson print json.loads (Datajson) 3, encoding process, list and tuple in Python are converted to JSON arrays, and after decoding, The JSON array is eventually transformed into a python list, whether it's a list or a tuple. Serialization and deserialization 1. Convert the Python class object to JSON format: Use the default parameter in the dumps () function Import Jsonclass Employee (objECT):d EF __init__ (self,name,age,sex,tel): Self.name = Nameself.age = Ageself.sex = Sexself.tel = tel# defines the serialization function inside the class Def ObjJ Son: return {' name ': Self.name, ' age ': self.age, ' sex ': self.sex, ' tel ': self.tel} e1 = Employee (' Andy ', ' 24 ', ' Male ', ' 131xxxxxxxx ') print json.dumps (E1,default=e1.objjson) #另一个更简单的方法e1 =employee (' Andy ', ' a ', ' Male ', ' 131xxxxxxxx ') # print json.dumps (e1,default=e1.objjson) print json.dumps (e1.__dict__) typically a class and its instances will have a __dict__ Property (unless the __slots__ attribute is added to the class), it is a dict type that stores the properties that are valid in a class or class instance.  2, JSON deserializes a class object JSON string into an instance of a class object or class, using the Object_hook parameter in the loads () method. Json.loads (Data,object_hook=jsontoclass) class Employee (object):d EF __init__ (Self,name,age,sex,tel): Self.name = Nameself.age = Ageself.sex = Sexself.tel = Teldef Objjson (self,obj_instance): return {' name ': obj_ Instance.name, ' age ': obj_instance.age, ' sex ': obj_instance.sex, ' tel ': obj_instance.tel} e1 = Employee (' Andy ', ' (' Male ', ' 131xxxxxxxx ') print json.dumps (e1.__dict__) #fucn (E1) print E1.__dict__ def Jsontoclass (DICTVAR): Return Employee (dictvar[' name '],dictvar[' age '],dictvar[' sex '],dictvar[' tel ']) Jsondate = {"Age": "+", "tel": " 131xxxxxxxx "," name ":" Andy "," Sex ":" male "}e = Json.loads (jsondate,object_hook=jsontoclass) print Eprint e.name Four , Python type JSON string type dict ObjectList, tuple  ARRAYSTR, Unicode Stringint, long, float &NBS P numbertrue truefalse falsenone null
Python JSON encoding
