Python parsing json detailed

JSON functions

Use JSON functions to import the JSON library: import JSON.

Function description

Json.dumps to encode a Python object as a JSON string

Json.loads decoding encoded JSON strings to Python objects

Json.dumps

Grammar

Json.dumps (obj, Skipkeys=false, Ensure_ascii=true, Check_circular=true, Allow_nan=true, Cls=none, Indent=None, Separators=none, encoding= "Utf-8", Default=none, Sort_keys=false, **kw)

Instance

The following example encodes an array into JSON-formatted data:

#!/usr/bin/pythonimport Jsondata = {' number ': 6, ' name ': ' pythontab '}jsondata = json.dumps (data) Print Jsondata

The result of the above code execution is:

{"Number": 6, "name": "Pythontab"}

Note: You may find that after performing the above conversion, the data has not changed, here is to say: in JSON, double quotation marks are the symbol of the string split, single quotation marks are not standard.

Use parameters to sort and format the output of JSON data:

#!/usr/bin/pythonimport Jsondata = {' number ': 6, ' name ': ' pythontab '}jsondata = json.dumps (data, Sort_keys=true, indent= 4, separators= (', ', ': ')) print Jsondata

Output results

{    "name": "Pythontab",    "number": 6}

Python primitive type conversion table to JSON type:

Python	JSON
Dict	Object
List, tuple	Array
STR, Unicode	String
int, long, float	Number
True	True
False	False
None	Null

Json.loads

The json.loads is used to decode JSON data. The function returns the data type of the Python field.

Grammar

Json.loads (s[, encoding[, cls[, object_hook[, parse_float[, parse_int[, parse_constant[, object_pairs_hook[, **kw]] [] ]]])

Instance

The following example shows how Python decodes a JSON object:

#!/usr/bin/pythonimport jsonjsondata = ' {' number ': 6, ' name ': ' Pythontab '} ' str = json.loads (jsondata) Print str

The result of the above code execution is:

{u ' number ': 6, U ' name ': U ' pythontab '}

JSON type conversion to Python type comparison table:

JSON	Python
Object	Dict
Array	List
String	Unicode
Number (int)	int, long
Number (real)	Float
True	True
False	False
Null	None

Using third-party libraries: Demjson

Demjson is a third-party module library of Python that can be used to encode and decode JSON data, including the Jsonlint formatting and validation functions.

Environment configuration

Before using Demjson encoding or decoding JSON data, we need to install the Demjson module first.

Method 1: Source code Installation

$ TAR-XVZF demjson-2.2.4.tar.gz

$ CD demjson-2.2.4

$ python setup.py Install

Method 2: Use PIP installation directly

Pip Install Demjson

JSON functions

Function description

Encode to encode a Python object as a JSON string

Decode can use the Demjson.decode () function to decode JSON data. The function returns the data type of the Python field.

Encode syntax

Demjson.encode (self, obj, nest_level=0)

Decode syntax

Demjson.decode (self, txt)