Python读取环境变量的方法和自定义类分享

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"])

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()