Python pathlib的使用方法

from pathlib import Path

# 创建相对路径对象
current_file = Path('example.py')

# 创建绝对路径对象（跨平台）
home_dir = Path.home()
project_dir = home_dir / 'projects' / 'my_project'

file_path = Path('data/reports/sales_2023.csv')

file_path.name     # 'sales_2023.csv'
file_path.stem     # 'sales_2023'
file_path.suffix   # '.csv'
file_path.parent   # PosixPath('data/reports')
file_path.parts    # ('data', 'reports', 'sales_2023.csv')
file_path.absolute()  # 解析为绝对路径

# 推荐：运算符 /
config_path = Path('config') /'settings'/'dev.yaml'

# joinpath
log_path = Path('logs').joinpath('app', 'error.log')

# 动态多段
parts = ['data', '2023', 'Q3', 'report.xlsx']
report_path = Path.cwd().joinpath(*parts)

file_path = Path('src/utils/__init__.py')

file_path.exists()   # 是否存在
file_path.is_file()  # 文件
file_path.is_dir()   # 目录
file_path.resolve()  # 绝对路径（解析符号链接）
file_path.as_uri()   # file:// URI

# 文本
config_file = Path('config/settings.ini')
config_file.write_text('[DEFAULT]\nlanguage=en\n', encoding='utf-8')
content = config_file.read_text(encoding='utf-8')

# 二进制
image_path = Path('static/images/logo.png')
binary_data = image_path.read_bytes()

# 追加写入
withconfig_file.open('a', encoding='utf-8') asf:
    f.write('\n[Database]\nhost=localhost')

# 递归创建
data_dir = Path('data/raw/2023')
data_dir.mkdir(parents=True, exist_ok=True)

# 一级遍历
foriteminPath('src').iterdir():
    ifitem.is_file():
        print(f"文件: {item.name}")
    elifitem.is_dir():
        print(f"目录: {item.name}")

# 递归 glob
forpy_fileinPath('.').rglob('*.py'):
    print(py_file.absolute())

(Path('data')
 .mkdir(exist_ok=True)
 .joinpath('processed')
 .mkdir(exist_ok=True)
 .joinpath('results.json')
 .write_text('{"status": "success"}', encoding='utf-8'))

fromdatetimeimportdatetime

log_file = Path('/var/log/app.log')
stats = log_file.stat()

print(f"大小: {stats.st_size / 1024:.2f} KB")
print(f"修改时间: {datetime.fromtimestamp(stats.st_mtime)}")
print(f"权限: {oct(stats.st_mode)[-3:]}")

forreportinPath('reports').glob('2023_Q[1-4]_*.xlsx'):
    quarter = report.stem.split('_')[1]
    print(f"处理第 {quarter} 季度报告: {report}")

fortxt_fileinPath('docs').glob('*.txt'):
    new_name = txt_file.with_suffix('.md')
    txt_file.rename(new_name)
    print(f"重命名: {txt_file} -> {new_name}")

config_dir = Path.home() /'.config'/'my_app'
config_files = list(config_dir.glob('*.conf'))

settings = {}
forconf_fileinconfig_files:
    forlineinconf_file.read_text(encoding='utf-8').splitlines():
        if'='inline:
            key, value = line.split('=', 1)
            settings[key.strip()] = value.strip()

importtempfile
frompathlibimportPath

defprocess_data(csv_path: Path):
    """占位：业务处理逻辑"""
    pass

withtempfile.TemporaryDirectory() astmp:
    tmp_path = Path(tmp)
    tmp_file = tmp_path/'temp_data.csv'
    tmp_file.write_text("id,name,value\n1,test,100", encoding='utf-8')
    process_data(tmp_file)
# 退出 with 块后目录自动删除

importos

defload_resource(relative_path: str) ->str:
    base_path = Path(__file__).parent
    resource_path = (base_path/relative_path).resolve()
    returnresource_path.read_text(encoding='utf-8')

importyaml

defload_config(env: str) ->dict:
    config_path = Path("config") /env/"settings.yaml"
    ifnotconfig_path.exists():
        raiseFileNotFoundError(config_path)

    backup = config_path.with_suffix('.yaml.bak')
    backup.write_text(config_path.read_text(encoding='utf-8'), encoding='utf-8')
    returnyaml.safe_load(config_path.read_text(encoding='utf-8'))

importtime
fromdatetimeimportdatetime

defarchive_old_logs(log_dir: Path, days: int = 30):
    cutoff = time.time() -days*86400
    archive_dir = log_dir/"archives"
    archive_dir.mkdir(exist_ok=True)

    forlog_fileinlog_dir.glob("*.log"):
        iflog_file.stat().st_mtime<cutoff:
            ts = datetime.fromtimestamp(log_file.stat().st_mtime).strftime('%Y%m%d')
            new_name = f"{log_file.stem}_{ts}{log_file.suffix}"
            log_file.rename(archive_dir/new_name)

defsetup_project_structure(base_dir: Path):
    dirs = [
        base_dir/"src",
        base_dir/"tests",
        base_dir/"docs",
        base_dir/"data/raw",
        base_dir/"data/processed",
        base_dir/"logs",
    ]
    fordindirs:
        d.mkdir(parents=True, exist_ok=True)
        (d/".gitkeep").touch()

    readme = base_dir/"README.md"
    ifnotreadme.exists():
        readme.write_text("# Project Documentation\n\n...", encoding='utf-8')

importos

defsecure_delete(file_path: Path, passes: int = 3):
    ifnotfile_path.is_file():
        raiseValueError(f"{file_path} 不是文件")

    size = file_path.stat().st_size
    withfile_path.open('br+') asf:
        for_inrange(passes):
            f.seek(0)
            f.write(os.urandom(size))
        f.flush()
        os.fsync(f.fileno())

    file_path.unlink()