User reading and writing to a file

Question

i am trying to write a program that if a user press 1, it reads the file, if 2, it write to the file and if 3, it erase the file. Unfortunately, the code stop working after the first input from user. Is it possible to write a function for that?

while True:
    print("(1) Read the notebook")
    print("(2) Add note")
    print("(3) Empty the notebook")
    print("(4) Quit")

    user_input = input("Please select one: ")

    if user_input == 1:
        readfile = open("notebook.txt","r")
        content = readfile.read()
        print(content)
        readfile.close()

    elif user_input == 2:
        new_input = input("Write a new note: ")
        readfile = open("notebook.txt", "a")
        readfile.write(new_input)
        readfile.close()

    elif user_input == 3:
        readfile = open("notebook.txt", "w")
        readfile.close()

    elif user_input == 4:
        break

print("Notebook shutting down, thank you.")

"Unfortunately, the code doesn't work as i intend." Why not? What's breaking? — TayTay, Jul 24 '18 at 14:30
`input` always returns a string. You need to convert it to `int` or check for string values e.g. `if user_input == '1':` — roganjosh, Jul 24 '18 at 14:33
@JosephFarah The code is works such that when the user press 1, the code reads the file, when 2 is entered it write to the file and when 3 is entered it deletes the file while 4 exit the program. — superv, Jul 24 '18 at 14:55

score 0 · Accepted Answer · answered Jul 24 '18 at 14:34

0

Python3 does not have separate raw_input() and input() functions for returning ints and strings. It only has input(), which returns a string. You are attempting to compare the output of input() (a string) to an int, for example on this line:

if user_input == 1:

The solution is to use the int() function to get the types right, i.e.

if int(user_input) == 1:

More reading

Source 1

Source 2

answered Jul 24 '18 at 14:34

Joseph Farah

2,463
2
25
36

Thanks. I did use use int() earlier but the code didn't run at all. I will try that and see. – superv Jul 24 '18 at 14:50
1

@superv could you please update your original question with what you mean by "not run at all"? – Joseph Farah Jul 24 '18 at 14:55
Thanks guys. I saw i did not add a line of code earlier on. i have done that and also add the int() conversion. The code seems to work but with few errors which i cant seems to find. here is the code: – superv Jul 24 '18 at 15:04

score 0 · Answer 2 · answered Jul 24 '18 at 14:39

0

The problem is that your user input should be an int. Use this instead :=>"user_input = int(input("Please select one: "))" And also you cannot write an integer to a file so use this: => "readfile.write("user_input")" or convert your user input to string before writing to the file.

answered Jul 24 '18 at 14:39

Chinonso Ngwu

9
3

Thanks. I did use use int() earlier but the code didn't run at all. – superv Jul 24 '18 at 14:50
1

`readfile.write("user_input")` will not do what they want. That's not how to convert to string – roganjosh Jul 24 '18 at 14:50
@roganjosh is right, its just going to write the string "user_input" to the file. – Joseph Farah Jul 24 '18 at 14:56
it's just an example – Chinonso Ngwu Jul 24 '18 at 15:01
I did ask him to convert to string before writing to file – Chinonso Ngwu Jul 24 '18 at 15:01
@superv use this to get the exact value you want wrriten to the file:=> readfile.write(str(user_input)) – Chinonso Ngwu Jul 24 '18 at 15:06
@superv kindly mark as answered – Chinonso Ngwu Jul 24 '18 at 15:07
I have fixed that part. Thanks Chinonso. – superv Jul 24 '18 at 15:07
I have edited the code. Most part has worked as i expected but now am getting this error : Incorrect output: your program printed "3(1)", but should have printed "3Notes". What might the problem? – superv Jul 24 '18 at 15:12
if you run your code with option 1 first you will get an error as you are trying to read a file that doesn't exist. – Chinonso Ngwu Jul 24 '18 at 15:28
post your new code let me check – Chinonso Ngwu Jul 24 '18 at 15:28
post your code let me check here – Chinonso Ngwu Jul 24 '18 at 15:33
@ChinonsoNgwu I have solved it. Thanks man. Which side your come from naija? – superv Jul 24 '18 at 18:49

User reading and writing to a file

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