Overview
This article will explain what JSON is and how to use the "json" module in Python to convert a string data type to a dictionary data type and convert a dictionary data type to a string data type.
Materials
Computer
Python
- Modules used: json
Terminal, Shell or IDE
What is JSON
JSON stands for Javascript object notation. (1) This format of text is used to contain and save a lot of information that can be analyzed for future use. JSON's data type is a dictionary which makes it useful for storing a lot of information.
Why use the Python "json" Module
The "json" module is useful for converting string data type variables to dictionary data type variables and converting dictionary data type variables to string data type variables.
How to use the "json" Module
Converting a String to a Dictionary
The json method "json.loads()" converts a string to a dictionary.
import json
a_string = '{"planet":"Earth", "animal":["cat", "dog"], "numbers":{"One":1, "Two":2}}'
change_string_to_dictionary = json.loads(a_string)
print(type(change_string_to_dictionary))
print(change_string_to_dictionary["planet"])
print(change_string_to_dictionary["animal"][0])
print(change_string_to_dictionary["numbers"]["One"])
Converting a Dictionary to a String
The json method "json.dumps()" converts a dictionary to a string.
import json
a_dictionary = {"first_key": 13, "second_key": ["sample_text", 15]}
change_dictionary_to_string = json.dumps(a_dictionary)
print(type(change_dictionary_to_string))
print(change_dictionary_to_string)
Printing all the Keys and Values from a Dictionary
By using a for-loop, it is also possible to print all the keys and values from a Dictionary.
import json
a_string = '{"planet":"Earth", "animal":["cat", "dog"], "numbers":{"One":1, "Two":2}}'
change_string_to_dictionary = json.loads(a_string)
for key in change_string_to_dictionary:
print(key) #Prints all keys
print(change_string_to_dictionary[key]) #Prints all values
Sources
https://www.w3schools.com/python/python_json.asp (1)