Python中正反斜杠的正确使用方法

# Windows路径示例
windows_path = "C:\\Users\\Admin\\Documents\\file.txt"

# Unix/Linux路径示例
unix_path = "/home/user/documents/file.txt"

path = r"C:\Users\Admin\Documents\file.txt"
print(path)  # 输出: C:\Users\Admin\Documents\file.txt

path = "C:\\Users\\Admin\\Documents\\file.txt"
print(path)  # 输出: C:\Users\Admin\Documents\file.txt

path = "C:/Users/Admin/Documents/file.txt"
print(path)  # 输出: C:/Users/Admin/Documents/file.txt

import os

# 自动使用当前系统的正确分隔符
path = os.path.join("folder", "subfolder", "file.txt")
print(path)  
# Windows输出: folder\subfolder\file.txt
# Unix输出: folder/subfolder/file.txt

# 普通字符串
s1 = "Hello\nWorld"  
print(s1)
# 输出:
# Hello
# World

# 原始字符串
s2 = r"Hello\nWorld"  
print(s2)  # 输出: Hello\nWorld

# 正则表达式中的使用
import re

# 不使用原始字符串
pattern1 = "\\d+\\.\\d+"  # 匹配数字如1.23

# 使用原始字符串更清晰
pattern2 = r"\d+\.\d+"  
print(re.search(pattern2, "Price: 12.99"))  # 匹配成功

# Windows系统中这样写会报错
file = open("C:\Users\new\file.txt")  # \n被解释为换行符

# 想匹配反斜杠本身
pattern = "\"  # 语法错误

# 方法1：双反斜杠
pattern = "\\\\"

# 方法2：使用原始字符串（推荐）
pattern = r"\\"

url = "https://www.example.com/path/to/resource"

# 分割URL路径
from urllib.parse import urlparse
result = urlparse(url)
print(result.path)  # 输出: /path/to/resource

from pathlib import Path
file_path = Path("folder") / "subfolder" / "file.txt"