python 读取修改环境变量

使用os.environ来读取和修改环境变量：

import os

print (os.environ["TEMP"])

mydir = "c:\\mydir"

os.environ["MYDIR"] = mydir

print (os.environ["MYDIR"])

pathV = os.environ["PATH"]

print (pathV)

os.environ["PATH"]= mydir + ";" + os.environ["PATH"]

print (os.environ["PATH"])

自定义的python的环境变量类：

import os

class MyEnv:

def __init__(self):

self.envFile = "c:\\myenv.txt"

self.envs = {}

def SetEnvFile(self, filename) :

self.envFile = filename

def Save(self) :

outf = open(self.envFile, "w")

if not outf:

print ("env file cannot be opened for write!")

for k, v in self.envs.items() :

outf.write(k + "=" + v + "\n")

outf.close()

def Load(self) :

inf = open(self.envFile, "r")

if not inf:

print ("env file cannot be opened for open!")

for line in inf.readlines() :

k, v = line.split("=")

self.envs[k] = v

inf.close()

def ClearAll(self) :

self.envs.clear()

def AddEnv(self, k, v) :

self.envs[k] = v

def RemoveEnv(self, k) :

del self.envs[k]

def PrintAll(self) :

for k, v in self.envs.items():

print ( k + "=" + v )

if __name__ == "__main__" :

myEnv = MyEnv()

myEnv.SetEnvFile("c:\\myenv.txt")

myEnv.Load()

myEnv.AddEnv("MYDIR", "c:\\mydir")

myEnv.AddEnv("MYDIR2", "c:\\mydir2")

myEnv.AddEnv("MYDIR3", "c:\\mydir3")

myEnv.Save()

myEnv.PrintAll()