python：如何仅使用字符串名称将变量传递给函数

Question

I'm interacting with a relatively complex program and putting a GUI on it to issue commands. I made up a simple example which I think demonstrates the problem. I know what parameters need to be passed to issue a command but I will only be able to get them as strings.

There are hundreds of commands with different return values that I get dynamically, but this is one example what I can get back when I pass a command ID

def get_command_vars(commandID = None):
    if commandID == '0x4F':
    return [['mode', '16bits'], ['seconds', '8bits']]


def issueMyCommand(commandID = None):
    commandParameters = get_command_vars(command=0x4F)

commandParameters tells me that the parameters for this command are mode and seconds, but they are strings

commandParm_1 = commandParameters[0][0] # 'mode'
commandParm_2 = commandParameters[1][0] # 'seconds'

>get User Input from the gui to pass to issuetheCommand
input1 = getinputEntry1() # this is the 'mode' value, e.g., 8
input2 = getinputEntry2() # this is the 'seconds' value, e.g., 14

I have the values to pass from the user input but I don't know how to pass them to the function since I only have the variables as strings, ie'mode' and 'seconds'

c = issueTheCommand(mode = input1, seconds = input2)

this command format will change based on the parameter types from get_command_vars, so it could be 'count', 'datalength', 'milliseconds, 'delay', etc

@sberry - actually the user input values are what will be passed with mode and seconds. the 16bits and 8 bits doesn't really come into play here. I'm trying to do this without changing the format that "issueTheCommand" function is expecting if possible. the way I issue it now looks like this: c = issueTheCommand(mode = 8, seconds = 14). i don't think it will take a dict?

Answer 1

If my comment to your question is what you are after then perhaps using a dictionary as key-word arguments would work for you.

>>> def issueTheCommand(mode, seconds):
...     print mode, seconds
...
>>> issueTheCommand(**{"mode": "16bits", "seconds": "8bits"})
16bits 8bits

Answer 2

Arguments specified as keywords can be picked up as a dict. Conversely, keyword arguments can be provided as a dict. Look:

>>> def a(**b):   # Pick up keyword args in a dict named b.
...   print(b)
... 
>>> a(x=1, y=2)
{'y': 2, 'x': 1}
>>> c = {'y': 2, 'x': 1}
>>> a(**c)
{'y': 2, 'x': 1}