电脑上安装两个版本的python时，迅速切换环境，python切换,通过修改注册表达到切换环

电脑上安装两个版本的python时，迅速切换环境，python切换,通过修改注册表达到切换环

通过修改注册表达到切换环境的目的，包括双击py、pyw文件时默认程序、右键Edit with IDLE时默认编辑器的修改，本例子是2.7与3.2的切换。

import win32api,win32consubkeys = ["Python.CompiledFile\\\\shell\\\\open\\\\command",           "Python.File\\\\shell\\\\Edit with IDLE\\\\command",           "Python.File\\\\shell\\\\open\\\\command",           "Python.File\\\\shell\\\\Run in interactive mode\\\\command",           "Python.NoConFile\\\\shell\\\\Edit with IDLE\\\\command",           "Python.NoConFile\\\\shell\\\\open\\\\command",           "Python.NoConFile\\\\shell\\\\Run in interactive mode\\\\command"]key = win32api.RegOpenKey(win32con.HKEY_CLASSES_ROOT,                          subkeys[0], 0, win32con.KEY_READ)version = win32api.RegQueryValue(key, "")[9:11]version2 = '27' if version=='32' else '32'print "The current version is Python %s,\\nDo you want to change it \\to %s?"%(version, version2)c = raw_input("Y/N?\\n")if c=="N" or c=="n":    print "Nothing changed!"elif c=="Y" or c=="y":    a,b=("27","32") if version=="27" else ("32","27")    for subkey in subkeys:        key = win32api.RegOpenKey(win32con.HKEY_CLASSES_ROOT, subkey,                                  0, win32con.KEY_ALL_ACCESS)        s = win32api.RegQueryValue(key, "")        win32api.RegSetValue(key, "", win32con.REG_SZ, s.replace(a, b))        win32api.RegCloseKey(key)    print "Done!"else:    print "what's it?"raw_input("Press Enter to exit")#该片段来自于http://byrx.net