How do I read from an open file?

Question

I'm trying to write a program that can store the contents of a file into a variable chosen by the user. For example, the user would choose a file located in the current directory and would then choose the variable they wanted to store it in. This is a segment of my code so far.

print("What .antonio file do you want to load?")
loadfile = input("")
open(loadfile, "r")

print("Which variable do you want to load it for? - list_1, list_2, list_3")
whichvariable = input("") 

if whichvariable == "list_1":
    list_1 = loadfile.read()
elif whichvariable == "list_2":
    list_2 = loadfile.read()
elif whichvariable == "list_3":
    list_3 = loadfile.read()
else:
    print("ERROR")

When I input that loadfile = list1.antonio (which is an existing file) and whichvariable = list_1 it throws me this error:

Traceback (most recent call last):
  File "D:\Antonio\Projetos\Python\hello.py", line 29, in <module>
    list_1 = loadfile.read()
AttributeError: 'str' object has no attribute 'read'

I have tried all sorts of things and I haven't find a solution.

You have to assign the result of `open()` to a variable, and read from that. — Barmar, Nov 17 '19 at 16:06
loadfile is just the *name* of the file, you still need to open it... — jonrsharpe, Nov 17 '19 at 16:07
Thank you so much! Now I see what I did wrong. I'm new and i'm also 13 so sometimes I dont understand the syntax of some commands very well. Thanksss! — ClashLarinco Gamer, Nov 17 '19 at 16:14
@ClashLarincoGamer since you are new, please use the `with` clause in the answer below, not the first option. — Error - Syntactical Remorse, Nov 17 '19 at 16:22

score -1 · Accepted Answer · answered Nov 17 '19 at 16:14

You need to store result of open into a variable, and do read method from that variable.

Here the fix of your code:

print("What .antonio file do you want to load?")
loadfile = input("")
loadfile = open(loadfile, "r") # you forget to store the result of open into loadfile

print("Which variable do you want to load it for? - list_1, list_2, list_3")
whichvariable = input("") 

if whichvariable == "list_1":
    list_1 = loadfile.read()
elif whichvariable == "list_2":
    list_2 = loadfile.read()
elif whichvariable == "list_3":
    list_3 = loadfile.read()
else:
    print("ERROR")

Dont forget to close your loadfile opened file.

And better

print("What .antonio file do you want to load?")
loadfile = input("")
with open(loadfile, "r") as openedfile:

    print("Which variable do you want to load it for? - list_1, list_2, list_3")
    whichvariable = input("") 

    if whichvariable == "list_1":
        list_1 = loadfile.read()
    elif whichvariable == "list_2":
        list_2 = loadfile.read()
    elif whichvariable == "list_3":
        list_3 = loadfile.read()
   else:
       print("ERROR")

You never close `loadfile` in the first example. Though this isn't needed with a `with` statement, if you don't use a `with` clause then you need to close the file. — Error - Syntactical Remorse, Nov 17 '19 at 16:23

How do I read from an open file?

1 Answers1