如何将文件逐行读入列表？

Question

如何在 Python 中读取文件的每一行并将每一行作为一个元素存储在列表中？

我想逐行读取文件并将每一行附加到列表的末尾。

Answer 1

此代码会将整个文件读入内存：

with open(filename) as file:
    lines = file.readlines()

如果要删除每行末尾的所有空白字符（换行符和空格），请改用：

with open(filename) as file:
    lines = [line.rstrip() for line in file]

（这避免了从 分配额外的列表file.readlines()。）

如果您正在处理一个大文件，那么您应该逐行阅读和处理它：

with open(filename) as file:
    for line in file:
        print(line.rstrip())

在 Python 3.8 及更高版本中，您可以使用带有海象运算符的 while 循环，如下所示：

with open(filename) as file:
    while line := file.readline():
        print(line.rstrip())

Answer 2

请参阅输入和输出：

with open('filename') as f:
    lines = f.readlines()

或剥离换行符：

with open('filename') as f:
    lines = [line.rstrip('\n') for line in f]

Answer 3

请参阅输入和输出：

with open('filename') as f:
    lines = f.readlines()

或剥离换行符：

with open('filename') as f:
    lines = [line.rstrip('\n') for line in f]