python os.argv[]

Posted on 2016-01-15 10:56  心在北方  阅读(1060)  评论(0编辑  收藏  举报

python 111.py 

111.py  就是os.argv[0]

 

引用网上的资料

sys.argv[]是用来获取命令行参数的,sys.argv[0]表示代码本身文件路径;比如在CMD命令行输入 “python  test.py -help”,那么sys.argv[0]就代表“test.py”。
sys.startswith() 是用来判断一个对象是以什么开头的,比如在python命令行输入“'abc'.startswith('ab')”就会返回True

以下实例参考:

#!/usr/local/bin/env python

import sys
def readfile(filename):
    '''Print a file to the standard output.'''
    f = file(filename)
    while True:
          line = f.readline()
          if len(line) == 0:
             break
          print line,
    f.close()

print "sys.argv[0]---------",sys.argv[0]                                    
print "sys.argv[1]---------",sys.argv[1]                                    
print "sys.argv[2]---------",sys.argv[2]
# Script starts from here
if len(sys.argv) < 2:
    print 'No action specified.'
    sys.exit()

if sys.argv[1].startswith('--'):
   option = sys.argv[1][2:]
   # fetch sys.argv[1] but without the first two characters
   if option == 'version':
      print 'Version 1.2'
   elif option == 'help':
      print '''"
           This program prints files to the standard output.
           Any number of files can be specified.
           Options include:
           --version : Prints the version number
           --help    : Display this help'''
   else:
       print 'Unknown option.'
       sys.exit()
else:
    for filename in sys.argv[1:]:
        readfile(filename)

执行结果:# python test.py --version help
sys.argv[0]--------- test.py
sys.argv[1]--------- --version
sys.argv[2]--------- help
Version 1.2

注意:sys.argv[1][2:]表示从第二个参数,从第三个字符开始截取到最后结尾,本例结果为:version

Copyright © 2024 心在北方
Powered by .NET 9.0 on Kubernetes