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一、简介：
argparse是python用于解析命令行参数和选项的标准模块，用于代替已经过时的optparse模块。argparse模块的作用是用于 解析命令行参数，例如python parseTest.py input.txt output.txt --user=name --port=8080。
二、使用步骤：
1：import argparse
2：parser = argparse.ArgumentParser()
3：parser.add_argument()
4：parser.parse_args()
解释：首先导入该模块；然后创建一个解析对象；然后向该对象中添加你要关注的命令行参数和选项，每一个add_argument方法对应一个你要关注的参数或选项；最后调用parse_args()方法进行解析；解析成功之后即可使用，下面简单说明一下步骤2和3。
三、方法ArgumentParser(prog=None, usage=None,description=None, epilog=None, parents=[],formatter_class=argparse.HelpFormatter, prefix_chars=‘-‘,fromfile_prefix_chars=None, argument_default=None,conflict_handler=‘error‘, add_help=True)
这些参数都有默认值，当调用parser.print_help()或者运行程序时由于参数不正确(此时python解释器其实也是调用了pring_help()方法)时，会打印这些描述信息，一般只需要传递description参数，如上。
四、方法add_argument(name or flags...[, action][, nargs][, const][, default][, type][, choices][, required][, help][, metavar][, dest])
其中：
name or flags：命令行参数名或者选项，如上面的address或者-p,--port.其中命令行参数如果没给定，且没有设置defualt，则出错。但是如果是选项的话，则设置为None
nargs：命令行参数的个数，一般使用通配符表示，其中，‘?‘表示只用一个，‘*‘表示0到多个，‘+‘表示至少一个
default：默认值
type：参数的类型，默认是字符串string类型，还有float、int等类型
help：和ArgumentParser方法中的参数作用相似，出现的场合也一致
1 import argparse 2 3 def parse_args(): 4 description = usage: %prog [options] poetry-file 5 6 This is the Slow Poetry Server, blocking edition. 7 Run it like this: 8 9 python slowpoetry.py 10 11 If you are in the base directory of the twisted-intro package, 12 you could run it like this: 13 14 python blocking-server/slowpoetry.py poetry/ecstasy.txt 15 16 to serve up John Donne‘s Ecstasy, which I know you want to do. 17 18 19 parser = argparse.ArgumentParser(description = description) 20 21 help = The addresses to connect. 22 parser.add_argument(‘addresses‘,nargs = ‘*‘,help = help) 23 24 help = The filename to operate on.Default is poetry/ecstasy.txt 25 parser.add_argument(‘filename‘,help=help) 26 27 help = The port to listen on. Default to a random available port. 28 parser.add_argument(‘-p‘,--port‘, type=int, help=help) 29 30 help = The interface to listen on. Default is localhost. 31 parser.add_argument(‘--iface‘, help=help, default=‘localhost‘) 32 33 help = The number of seconds between sending bytes. 34 parser.add_argument(‘--delay‘, type=float, help=help, default=.7) 35 36 help = The number of bytes to send at a time. 37 parser.add_argument(‘--bytes‘, type=int, help=help, default=10) 38 39 args = parser.parse_args(); 40 return args 41 42 if __name__ == ‘__main__‘: 43 args = parse_args() 44 45 for address in args.addresses: 46 print ‘The address is : %s .‘ % address 47 48 print ‘The filename is : %s .‘ % args.filename 49 print ‘The port is : %d.‘ % args.port 50 print ‘The interface is : %s.‘ % args.iface 51 print ‘The number of seconds between sending bytes : %f‘% args.delay 52 print ‘The number of bytes to send at a time : %d.‘ % args.bytes 53
运行该脚本：python test.py --port 10000 --delay 1.2 127.0.0.1 172.16.55.67 poetry/ecstasy.txt
输出为：
The address is : 127.0.0.1 .
The address is : 172.16.55.67 .
The filename is : poetry/ecstasy.txt .
The port is : 10000.
The interface is : localhost.
The number of seconds between sending bytes : 1.200000
The number of bytes to send at a time : 10.
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原文地址：http://www.cnblogs.com/victorwu/p/5762665.html
