ошибка operation on closed file — операция над закрытым файлом
Ошибка ValueError: I/O operation on closed file
Task exception was never retrieved future: <Task finished name=’Task-15′.
ValueError: I/O operation on closed file
Помогите пожалуйста получить выходные значения, я новичок и код работает с ошибкой # Python.
ValueError: I/O operation on closed file
Программа выполняет первый цикл корректно, в файл записываются данные. Следующие повторения.
Ошибка cannot perform this operation on a closed dataset
Доброго времени! Релизовывал алгоритм удаления пользователя из бд, почему-то пишет, что датасет.
Ошибка cannot perform this operation on a closed dataset
При выполнения кода: procedure TForm2.Button1Click(Sender: TObject); begin .
Автоматизируй это!
7540 / 4556 / 1206
Регистрация: 30.03.2015
Сообщений: 13,118
Записей в блоге: 29
Ципихович Эндрю, а можно еще меньше кода показать, чтобы совсем ничего понятно не было? ты 12 лет на форуме, е-мае.
Давай весь код, что такое ф, и как используется ф2, давай полный текст ошибки.
1525 / 494 / 58
Регистрация: 10.04.2009
Сообщений: 8,327
а про 12 лет, это Вы помните, или сейчас посмотрели? — можете не отвечать.
время идёт может уже 13?
Сообщение от Welemir1 
давай полный текст ошибки.
Traceback (most recent call last):
File «C:\pythonProject\sudrf.ru1.py», line 14, in
if ‘України’ in f1: f2 = r’d:\Downloads\пустой.js’
ValueError: I/O operation on closed file.
Сообщение от Welemir1
Давай весь код
пожалуйста
1 2 3 4 5 6 7 8
f1 = r'd:\Downloads\1. КК України_23.07.2020.htm' f1 = open(f1, 'r', encoding='utf-8') s1 = f1.read() f1.close() import re f2 = r'd:\Downloads\Global 6.1\js\data\replacesrussianSpeaking.js' if 'України' in f1: f2 = r'd:\Downloads\пустой.js'
How to fix ValueError: I/O operation on closed file in Python
Last Updated Apr 21, 2023
When working with files using Python code, you might get the following error:
- You manipulate the file outside of the with block
- You read or write to CSV files after the file is closed
This tutorial will show you examples that cause this error and how to fix them.
1. You manipulate the file outside of the with block
When you use the with statement to open a file, you need to perform operations on the file inside the with block.
The following code opens a text file named file.txt file and writes a line in that file:
If you try to write a second line outside of the with block as follows:
You’ll get this error:
To fix this error, you need to put the write operation inside the with block by indenting the code:
Python automatically closes the file when it reaches the end of the with block, so you need to make sure any code that has something to do with the file is inside the block.
Alternatively, you can also open the file without using the with statement as follows:
In the above code, the result of calling the open() function is stored in the f_obj variable.
Unlike when using the with statement, you can manipulate the file even when you include line breaks.
When you’re done processing the file, you need to call the close() method on the file object to avoid memory leaks.
Notice that if you read or write after calling the close() method, the same error will be raised.
2. Working with CSV files
The same error also appears no matter what file extension your file has. You might be opening a .csv or a .json file, this error still appears when you try to read or write outside the with block.
For example, you might have the following code to read a CSV file:
The for loop in the code above lacks an indent, so the same error is triggered.
To fix this, indent the for loop as follows:
Here’s an alternative syntax without the with statement:
Notice that you didn’t get the “I/O operation on closed file” error this time.
Summary
To sum it up, the ValueError: I/O operation on closed file occurs when you attempt to read from or write to a file that’s already been closed by Python.
To resolve this error, make sure that you’re executing a read or write operation on a file that’s still open. If you’re using the with statement, make sure that any operations on the file are done inside the statement.
Otherwise, make sure you’re not manipulating the file after calling the close() method.
I hope this tutorial is helpful. I’ll see you again in other articles! ��
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Что делать: ValueError: I/O operation on closed file?
Коротко: необходимо открыть картинку и этой картинкой заменить прошлую:
with open('avatar/' + f'', 'rb') as file: cat = types.InputMediaPhoto(file) await bot.edit_message_media(chat_id=call.from_user.id, message_id=call.message.message_id, media=cat)Но вылазиет ошибка — ValueError: I/O operation on closed file
Ошибка:
ERROR:asyncio:Task exception was never retrieved
future: exception=ValueError(‘I/O operation on closed file’)>
Traceback (most recent call last):
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\dispatcher\dispatcher.py», line 415, in _process_polling_updates
for responses in itertools.chain.from_iterable(await self.process_updates(updates, fast)):
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\dispatcher\dispatcher.py», line 235, in process_updates
return await asyncio.gather(*tasks)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\dispatcher\handler.py», line 116, in notify
response = await handler_obj.handler(*args, **partial_data)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\dispatcher\dispatcher.py», line 283, in process_update
return await self.callback_query_handlers.notify(update.callback_query)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\dispatcher\handler.py», line 116, in notify
response = await handler_obj.handler(*args, **partial_data)
File «C:\Users\User\Desktop\testsearchanon\main.py», line 871, in oz1
await bot.edit_message_media(chat_id=call.from_user.id, message_id=call.message.message_id, media=cat)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\bot\bot.py», line 2743, in edit_message_media
result = await self.request(api.Methods.EDIT_MESSAGE_MEDIA, payload, files)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\bot\base.py», line 231, in request
return await api.make_request(await self.get_session(), self.server, self.__token, method, data, files,
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiogram\bot\api.py», line 139, in make_request
async with session.post(url, data=req, **kwargs) as response:
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\client.py», line 1138, in __aenter__
self._resp = await self._coro
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\client.py», line 507, in _request
req = self._request_class(
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\client_reqrep.py», line 313, in __init__
self.update_body_from_data(data)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\client_reqrep.py», line 507, in update_body_from_data
body = body()
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\formdata.py», line 170, in __call__
return self._gen_form_data()
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\formdata.py», line 163, in _gen_form_data
self._writer.append_payload(part)
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\multipart.py», line 831, in append_payload
size = payload.size
File «C:\Users\User\AppData\Local\Programs\Python\Python310\lib\site-packages\aiohttp\payload.py», line 379, in size
return os.fstat(self._value.fileno()).st_size — self._value.tell()
ValueError: I/O operation on closed file
- Вопрос задан более года назад
- 4293 просмотра
How to fix “ValueError: I/O operation on closed file” in Python
The Python error “ValueError: I/O operation on closed file” happens when you try to do I/O operations (read, write, etc.) on a file that’s already been closed.
Here’s what the error looks like:
Traceback (most recent call last): File "/dwd/app.py", line 2, in for line in file: ValueError: I/O operation on closed file.
This quick guide explains why this error happens and how to fix it quickly.
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How to fix it?
This error usually happens for two reasons:
- Incorrect indentation
- Closing the file prematurely
Incorrect indentation
Incorrect indentation can cause the «ValueError: I/O operation on closed file» error when working with files in Python. Below are two scenarios leading to this error.
Scenario #1: closing the file inside a loop: Imagine you have a loop that reads data from a file.
However, you unintentionally close the file at the same indentation level as the loop, making it part of the loop.
As a result, when you try to read the second line of the file, you’ll get the error because the file was closed in the first iteration.
file = open('data.txt', 'r') for line in file: print(line) # file is closed here file.close()
In the above code, since file.close() is indented within the loop (by mistake), the file is closed prematurely, causing the error.
To fix this issue, move the file.close() outside the loop, and you’ll be good to go:
file = open('data.txt', 'r') for line in file: print(line) # Closing the file after the loop finishes file.close()
Scenario #2: Using the with statement: As you probably know, when you open a file using the with statement , you won’t have to close the file at the end. Python automatically closes the file for you once the execution block finishes executing.
That said, if you have an I/O operation outside the with block, you’ll run into the error since the file is closed.
Imagine we’re trying to read a CSV file using the with open(‘. ‘) syntax:
import csv with open('users.csv', 'r') as file: csv_reader = csv.reader(file) for row in csv_reader: print(row)
In the above example, we open a file using the with statement, where we create a CSV reader object to iterate over lines and print each line.
However, the for loop is indented outside of the with block, making it run after with statement closes the file.
To fix this issue, ensure all I/O operations are part of the with block:
import csv with open('keywords.csv', r) as file: csv_reader = csv.reader(file) for line in csv_reader: print(line)
Closing the file prematurely
Another common cause of this ValueError error is closing the file prematurely before performing any I/O operations.
This might happen if you’ve copied a code from another source, like Stackoverflow or another file but forget to reorder the lines.
Imagine you want to read data from a file and store it in a list.
file = open('file.txt', 'r') data = [] file.close() for line in file: data.append(line)
In the above example, file.close() appears before we read the lines from the file.
Placing file.close() fixes the issue instantly.
file = open('file.txt', 'r') data = [] for line in file: data.append(line) file.close()
You can also check if a file is closed
To check whether a file is closed, you can use the closed attribute of the respective file object. The closed attribute contains a boolean value indicating whether the file is open or closed.
Here’s an example:
file = open('example.txt', 'r') print(file.closed) # False file.close() print(file.closed) # True
You might find this attribute helpful when debugging your code.
Wrapping up
The Python error «ValueError: I/O operation on closed file» typically occurs when a file is closed prematurely or due to incorrect indentation.
It’s a simple rule; Just ensure the code that closes the file is executed after the I/O operations.
Alright, I think it does it! I hope you found this quick guide helpful.
Thanks for reading.
Reza Lavarian Hey �� I’m a software engineer, an author, and an open-source contributor. I enjoy helping people (including myself) decode the complex side of technology. I share my findings on Twitter: @rezalavarian
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