我正在尝试将列表作为参数传递给命令行程序。是否可以argparse选择将列表作为选项传递?
argparse
parser.add_argument('-l', '--list', type=list, action='store', dest='list', help='<Required> Set flag', required=True)
脚本调用如下
python test.py -l "265340 268738 270774 270817"
使用nargs选项或选项'append'设置action(取决于您希望用户界面的行为方式)。
nargs
'append'
action
纳尔格斯
parser.add_argument('-l','--list', nargs='+', help='<Required> Set flag', required=True) # Use like: # python arg.py -l 1234 2345 3456 4567
nargs='+'接受 1 个或多个参数,nargs='*'接受零个或多个。
nargs='+'
nargs='*'
附加
parser.add_argument('-l','--list', action='append', help='<Required> Set flag', required=True) # Use like: # python arg.py -l 1234 -l 2345 -l 3456 -l 4567
append您可以多次提供选项来建立列表。
append
不要用type=list!!!- 可能没有您想使用type=list的情况argparse。曾经。
type=list
让我们更详细地了解一些可能尝试执行此操作的不同方式以及最终结果。
import argparse parser = argparse.ArgumentParser() # By default it will fail with multiple arguments. parser.add_argument('--default') # Telling the type to be a list will also fail for multiple arguments, # but give incorrect results for a single argument. parser.add_argument('--list-type', type=list) # This will allow you to provide multiple arguments, but you will get # a list of lists which is not desired. parser.add_argument('--list-type-nargs', type=list, nargs='+') # This is the correct way to handle accepting multiple arguments. # '+' == 1 or more. # '*' == 0 or more. # '?' == 0 or 1. # An int is an explicit number of arguments to accept. parser.add_argument('--nargs', nargs='+') # To make the input integers parser.add_argument('--nargs-int-type', nargs='+', type=int) # An alternate way to accept multiple inputs, but you must # provide the flag once per input. Of course, you can use # type=int here if you want. parser.add_argument('--append-action', action='append') # To show the results of the given option to screen. for _, value in parser.parse_args()._get_kwargs(): if value is not None: print(value)
这是您可以期待的输出:
$ python arg.py --default 1234 2345 3456 4567 ... arg.py: error: unrecognized arguments: 2345 3456 4567 $ python arg.py --list-type 1234 2345 3456 4567 ... arg.py: error: unrecognized arguments: 2345 3456 4567 $ # Quotes won't help here... $ python arg.py --list-type "1234 2345 3456 4567" ['1', '2', '3', '4', ' ', '2', '3', '4', '5', ' ', '3', '4', '5', '6', ' ', '4', '5', '6', '7'] $ python arg.py --list-type-nargs 1234 2345 3456 4567 [['1', '2', '3', '4'], ['2', '3', '4', '5'], ['3', '4', '5', '6'], ['4', '5', '6', '7']] $ python arg.py --nargs 1234 2345 3456 4567 ['1234', '2345', '3456', '4567'] $ python arg.py --nargs-int-type 1234 2345 3456 4567 [1234, 2345, 3456, 4567] $ # Negative numbers are handled perfectly fine out of the box. $ python arg.py --nargs-int-type -1234 2345 -3456 4567 [-1234, 2345, -3456, 4567] $ python arg.py --append-action 1234 --append-action 2345 --append-action 3456 --append-action 4567 ['1234', '2345', '3456', '4567']
要点 :
action='append'
'*'
'+'
'?'
4
type
type=int
1:我不是说一般......我的意思是使用引号将 _列表传递给argparse_不是你想要的。