Everything about "dump" and "load" in Python JSON

General
1

So today I’m gonna teach you about the “dump” and “load” functions in the JSON module in Python.
First, you have to import.

from json import dump, load

Now, we’re gonna learn about “dumping”
So “dump” is a function in JSON which can add contents in a file
Here’s an example:

file = open("file_name.json", "w")
dump("file contents", file)

What that does is make a file (if it doesn’t exist already) with “file contents” inside it.
The file contents don’t have to be a string. It can a integer, floating point, list, and basically everything (as long as it’s an object).
There are 3 ways to “dump”

replace_file_contents = open("file_name.json", "w")
add_to_file_contents = open("file_name.json", "a")
create_file = open("file_name.json", "x")

# This creates a file (if it already exists, then you will get a FileExistsError)
dump(123, create_file)

# This replaces the contents of a file (if the file doesn't exist, then the program will create a new file)
dump(True, replace_file_contents)

# This adds content to the file (if the file doesn't exist, then the program will create a new file)
dump("string", add_to_file_contents)

Now we’re going to talk about “load”.
It is used to read files.
Here’s an example:

variable = load(open("file_name.json"))

That’s all for now, Bye!

4 Likes
2

Question, what’s the difference between dump(), dumps(), and load(), loads()? I always forget which one to use, and get a bunch of errors.

3 Likes
3

I use json.dumps() and json.loads() it just dumps or loads from/to a string i beleive

3 Likes
4

Suggestions:

  • Use with instead of raw open, which is considered extremely bad practice.
  • Using json. although being less efficient, more clarifies what it is doing in this context

dump and load use raw file objects, instead of dumps and loads, which use strings. dump and load are way more efficient afaik, and dumps and loads are way easier to remember once you realize the s stands for string.

2 Likes