问题
Is it possible to require that an argparse argument be one of a few preset values?
My current approach is would be to examine the argument manually and if it's not one of the allowed values call print_help() and exit.
Here's the current implementation:
...
parser.add_argument('--val',
help='Special testing value')
args = parser.parse_args(sys.argv[1:])
if args.val not in ['a','b','c']:
parser.print_help()
sys.exit(1)
It's not that this is particularly difficult, but rather that it appears to be messy.
回答1:
An argparse argument can be limited to specific values with the choices parameter:
...
parser.add_argument('--val',
choices=['a','b','c'],
help='Special testing value')
args = parser.parse_args(sys.argv[1:])
See the docs for more details.
来源：https://stackoverflow.com/questions/15836713/allowing-specific-values-for-an-argparse-argument