一、常用变量
常见变量如下图所示:
变量 | 说明 |
sys.version | 返回Python的版本号 |
sys.maxsize | 返回操作系统承载的最大int值 |
sys.maxunicode | 返回最大Unicode代码点值的整数 |
sys.path | 返回当前脚本path环境变量 |
sys.platform | 返回操作系统平台名称 |
sys.argv | 将脚本运行时的脚本名称以及参数作为一个list,并输出 |
sys.executable | 一个字符串，返回可执行文件的绝对路径 |
sys.version_info | 返回包含版本号的五个组件的元组 |
代码示例如下:
import sys
print(sys.version)
print(sys.maxsize)
print(sys.maxunicode)
print(sys.path)
print(sys.platform)
print(sys.argv)
print(sys.executable)
print(sys.version_info)输出:
3.11.5 (tags/v3.11.5:cce6ba9, Aug 24 2023, 14:38:34) [MSC v.1936 64 bit (AMD64)]
9223372036854775807
1114111
['D:\\pythonProject\\MyPythonProject\\test', 'D:\\pythonProject\\MyPythonProject', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\python311.zip', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\DLLs', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\site-packages', 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\site-packages\\pip-23.2.1-py3.11.egg']
win32
['D:\\pythonProject\\MyPythonProject\\test\\test.py']
C:\Users\qx\AppData\Local\Programs\Python\Python311\python.exe
sys.version_info(major=3, minor=11, micro=5, releaselevel='final', serial=0)二、常用方法
常用方法如下图所示:
方法 | 说明 |
sys.exit() | 程序退出 |
sys.modules | 返回系统导入的模块名称，key是模块名、value是模块 |
sys.modules.keys() | 返回所有已导入的模块名列表 |
sys.getdefaultencoding() | 返回Unicode实现使用的当前默认字符串编码名称 |
sys.getfilesystemencoding() | 返回用于在Unicode文件名和字节文件名之间进行转换的编码名称 |
sys.getsizeof() | 获取对象占用的内存大小 |
sys.exc_info() | 获取当前正在处理的异常类 |
sys.getwindowsversion() | 获取windows的版本 |
sys.stdin.readline() | 从标准输入读一行，会读取末尾的换行符 |
sys.stdout.write() | 向标准输出写入内容 |
代码示例如下:
import sys
print(sys.modules)
print(sys.modules.keys())
print(sys.getdefaultencoding())
print(sys.getfilesystemencoding())
# 获取对象占用内存大小
for obj in [int(), float()]:
print(sys.getsizeof(obj))
# 返回obj的引用计数
a = [1, 2, 3]
b = a
c = b
print(sys.getrefcount(a))
print(sys.exc_info())
print(sys.getwindowsversion())
sys.stdin.readline()
sys.stdout.write('hello')输出:
{'sys': <module 'sys' (built-in)>, 'builtins': <module 'builtins' (built-in)>, '_frozen_importlib': <module '_frozen_importlib' (frozen)>, '_imp': <module '_imp' (built-in)>, '_thread': <module '_thread' (built-in)>, '_warnings': <module '_warnings' (built-in)>, '_weakref': <module '_weakref' (built-in)>, 'winreg': <module 'winreg' (built-in)>, '_io': <module '_io' (built-in)>, 'marshal': <module 'marshal' (built-in)>, 'nt': <module 'nt' (built-in)>, '_frozen_importlib_external': <module '_frozen_importlib_external' (frozen)>, 'time': <module 'time' (built-in)>, 'zipimport': <module 'zipimport' (frozen)>, '_codecs': <module '_codecs' (built-in)>, 'codecs': <module 'codecs' (frozen)>, 'encodings.aliases': <module 'encodings.aliases' from 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\encodings\\aliases.py'>, 'encodings': <module 'encodings' from 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\encodings\\__init__.py'>, 'encodings.utf_8': <module 'encodings.utf_8' from 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\encodings\\utf_8.py'>, '_signal': <module '_signal' (built-in)>, '_abc': <module '_abc' (built-in)>, 'abc': <module 'abc' (frozen)>, 'io': <module 'io' (frozen)>, '__main__': <module '__main__' from 'D:\\pythonProject\\MyPythonProject\\test\\test.py'>, '_stat': <module '_stat' (built-in)>, 'stat': <module 'stat' (frozen)>, '_collections_abc': <module '_collections_abc' (frozen)>, 'genericpath': <module 'genericpath' (frozen)>, '_winapi': <module '_winapi' (built-in)>, 'ntpath': <module 'ntpath' (frozen)>, 'os.path': <module 'ntpath' (frozen)>, 'os': <module 'os' (frozen)>, '_sitebuiltins': <module '_sitebuiltins' (frozen)>, '_codecs_cn': <module '_codecs_cn' (built-in)>, '_multibytecodec': <module '_multibytecodec' (built-in)>, 'encodings.gbk': <module 'encodings.gbk' from 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\encodings\\gbk.py'>, '_distutils_hack': <module '_distutils_hack' from 'C:\\Users\\qx\\AppData\\Local\\Programs\\Python\\Python311\\Lib\\site-packages\\_distutils_hack\\__init__.py'>, 'site': <module 'site' (frozen)>}
dict_keys(['sys', 'builtins', '_frozen_importlib', '_imp', '_thread', '_warnings', '_weakref', 'winreg', '_io', 'marshal', 'nt', '_frozen_importlib_external', 'time', 'zipimport', '_codecs', 'codecs', 'encodings.aliases', 'encodings', 'encodings.utf_8', '_signal', '_abc', 'abc', 'io', '__main__', '_stat', 'stat', '_collections_abc', 'genericpath', '_winapi', 'ntpath', 'os.path', 'os', '_sitebuiltins', '_codecs_cn', '_multibytecodec', 'encodings.gbk', '_distutils_hack', 'site'])
utf-8
utf-8
28
24
4
(None, None, None)
sys.getwindowsversion(major=10, minor=0, build=19045, platform=2, service_pack='')
3
hello
