三种操作系统windows、Mac 和 Linux
不同的操作系统，文件连接所用正反斜线是不一致的。
Windows filenames:
C:\some_folder\some_file.txt
Most other operating systems:
/some_folder/some_file.txt
三种不同的拼接路径的方式
- 手动拼接
data_folder = "source_data/text_files/"
file_to_open = data_folder + "raw_data.txt"
f = open(file_to_open)
print(f.read())
这样写，你不能让每个操作系统都能顺利执行。
- os.path 模块
import os.path
data_folder = os.path.join("source_data", "text_files")
file_to_open = os.path.join(data_folder, "raw_data.txt")
f = open(file_to_open)
print(f.read())
此代码可以在各个平台顺利运行，但是反复使用os.path.join很啰嗦
- pathlib模块(Python3的标准支持)
python3.4+ 都自带标准库pathlib，所以不需要再通过pip3 安装
from pathlib import Path
data_folder = Path("source_data/text_files/")
file_to_open = data_folder / "raw_data.txt"
f = open(file_to_open)
print(f.read())
不用open读文件 file.read_text()
from pathlib import Path
data_folder = Path("source_data/text_files/")
file_to_open = data_folder / "raw_data.txt"
print(file_to_open.read_text())
文件及路径操作
from pathlib import Path
filename = Path("source_data/text_files/raw_data.txt")
print(filename.name)
# prints "raw_data.txt"
print(filename.suffix)
# prints "txt"
print(filename.stem)
# prints "raw_data"
if not filename.exists():
print("Oops, file doesn't exist!")
else:
print("Yay, the file exists!")
