file = open('/home/ubuntu/PycharmProjects/test.txt', 'r') res1 = file.read() file.close() 1. 2. 3. 结果: Hello python this is a test file count = 0 sum = 0 while count < 3: sum += 1 print("hello linux)" count += 1
然而,如果我们在关闭文件后再次尝试使用文件对象进行I/O操作,就会引发"io operation on closed file"错误。具体来说,如果我们尝试对已经关闭的文件对象调用任何I/O方法(如read()、write()、seek()等),Python就会引发这个错误。 错误示例 让我们来看一个例子,展示了如何触发"io operation on closed file"错误: ...
- **使用try/except块**：对于需要执行可能引发I/O操作错误的代码块，使用try/except块捕获异常并妥善处理。在编程过程中，遇到“ValueError: I/O operation on closed file”错误时，关键在于理解错误发生的背景和原因。通过遵循良好的资源管理实践、正确使用with语句、检查代码的缩进，并合理管理文件句柄...
解决Python 中由于在for循环中关闭文件发生的异常 ValueError: I/O operation on closed file 此示例说明如何在不使用 with 语句的情况下发生ValueError: I/O operation on closed file。 当 Python 脚本打开文件并在循环内写入内容时,它必须在程序结束时关闭。 但是ValueError: I/O operation on closed file可能是...
# rf.read() # with结束还去调用rf对象的读取操作方法,抛异常:ValueError: I/O operation on closed file.with open('target.txt', 'r', encoding='utf-8') as rf1, open('target1.txt', 'r', encoding='utf-8') as rf2: print(rf1.read()) print(rf2.read()) # print(rf1.read()) ...
解决Python 中由于在for循环中关闭文件发生的异常 ValueError: I/O operation on closed file 此示例说明如何在不使用 with 语句的情况下发生ValueError: I/O operation on closed file。 当 Python 脚本打开文件并在循环内写入内容时,它必须在程序结束时关闭。
In Python, we need to open a file first to perform any operations on it—we use the open() function to do so. Let's look at an example: Suppose we have a file named file1.txt. Opening a File in Python To open this file, we can use the open() function. file1 = open("...
Python“ValueError: I/O operation on closed file”发生在我们试图对一个关闭的文件执行操作时。 要解决该错误,需要确保在使用with open()语句时缩进尝试正确访问文件的代码。 看下面的代码 importcsvwithopen('employees.csv','w', newline='', encoding='utf-8')ascsvfile: ...
Python运行csv文件时报错 self._fieldnames = next(self.reader) ValueError: I/O operation on closed file. Python运行csv文件时报错,self._fieldnames = next(self.reader) ValueError: I/O operation on closed file.表示处理已经被关闭... 查看原文 ...
You can only read from and write to a Python file if the file is open. If you try to access or manipulate a file that has been closed, the “ValueError : I/O operation on closed file” appears in your code. In this guide, we talk about what this error means and why it is raise...