python - 在这种情况下是否需要关闭文件？

Question

如果我有:

fdata = open(pathf, "r").read().splitlines()

获取数据后文件会自动关闭吗？如果不是，我该如何关闭它，因为 fdata 不是句柄？

谢谢

Answer 1

使用

with open(pathf, "r") as r:
    fdata = r.read().splitlines()
# as soon as you leave the with-scope, the file is autoclosed, even if exceptions happen.

不仅仅是自动关闭，还有异常情况下的正确关闭。

独库:methods of file objects

It is good practice to use the with keyword when dealing with file objects. The advantage is that the file is properly closed after its suite finishes, even if an exception is raised at some point. Using with is also much shorter than writing equivalent try-finally blocks:

If you’re not using the with keyword, then you should call f.close() to close the file and immediately free up any system resources used by it.
If you don’t explicitly close a file, Python’s garbage collector will eventually destroy the object and close the open file for you, but the file may stay open for a while. Another risk is that different Python implementations will do this clean-up at different times.