Reading and writing in files

Question

So theres this exercise (Lesson 49.2) where i have to open a file, write in it, close it, open it again, read it and print it. How do i do it?

Answer 1

There are some examples in the lessons. What errors/ problems did you encounter? Can you show us your code?

Answer 2

Okay, in the beginning names is a list of strings.
You could use join() to make them one single string. If you use "\n" to join, you get the line breaks.
If you have the string like this, you can write it to the file.

Answer 3

Join is a built-in string method:
https://www.w3schools.com/JUMP_LINK__&&__python__&&__JUMP_LINK/ref_string_join.asp

Of course you can also loop through the list and concatenate the strings like "line 1" + "\n" + "line 2"

Answer 4

"\n".join(your_list)

Answer 5

names = ["John", "Oscar", "Jacob"]

file = open("names.txt", "w+")
file.write(("\n".join(names))
file.close()

file= open("names.txt", "r")
r = file.read()
print(r)
file.close()

file.close() is an invalid syntax, why?

Answer 6

In your 3rd line (file.write) is one opening bracket too many. Remove it.

Answer 7

tho i have never learned about join() except from the battles against people for exp
is there another way for me to make the same exercise but with the limited stuff i know

Answer 8

names = ["John", "Oscar", "Jacob"]

file = open("names.txt", "w+")
i = file.write(str(names))
file.close()

file= open("names.txt", "r")
r = file.read()
print(r)
file.close()

Answer 9

Your code shows no error.

It seems to be a pro project, I cannot see what the task is.
Please explain, what you are trying to do.

Answer 10

so i was given the list
names = ["John", "Oscar", "Jacob"]

and i was supposed to
complete the program to create a file where you write the names from the list, each on a nrw line, and seperatly output them

so the output should be
John
Oscar
Jacob

Answer 11

wait do i do .join(\n)?

Answer 12

alright thanks for the help!

Answer 13

alright it works

Answer 14

names = ["John", "Oscar", "Jacob"]

file = open("names.txt", "w+")
for i in names:
file.write(i+"\n")
file.close()
file= open("names.txt", "r")
print(file.read())
file.close()

Answer 15

Hello people, the topic is closed, but I was just going through this task, and solved it with the help of this code. And only then decided to take a look, after all, it was more correct. Many thanks to the last author of the comment.

names = ["John", "Oscar", "Jacob"]

file = open("names.txt", "w+")
conte = "{} {} {}".format(*names)
conte = conte.replace(" ", "\n")

file.writelines(conte)
file.close()

file= open("names.txt", "r")
print(file.read())
file.close()