I/O 为什么我的代码总是抛出错误

Question

i stored data in a binary file.

enter code here

code 1--

import pickle as p

d = []

for i in range(3):
 
   d1 = []
    st = input("enter student name")
    rl = int(input("student roll no"))
    d1.append(st)
    d1.append(rl)
    d.extend(d1)

f = open("alex.dat", "wb")
p.dump(d,f)
f.close()

and then i printed

code 2--

import pickle as p
d = []
f = open("students.dat", "rb")
while f:
    try:
        d = p.load(f)
        print(d)
    except EOFError:
        f.close()

output -- ['admin', 22, 'momo', 21, 'sudhanshu', 323] Traceback (most recent call last): File "C:\Users\admin\AppData\Roaming\JetBrains\PyCharmCE2021.3\scratches\scratch_2.py", line 6, in d = p.load(f) ValueError: peek of closed file

why valueError?

Answer 1

As @Maurice Mayer stated the while Condition is breaking your Code

You are writing in Code 1 everything in one file so you need just to load the file once. Checking the file-object which is already closed is breaking your Code 2

import pickle as p
d = None # Just to be sure
f = open("students.dat", "rb")

try:
    d = p.load(f)
    print(d)
except EOFError:
    f.close()

This should work