在Python中动态调用函数的方法是什么?

函数是一类对象。所以像这样:

def do_this():
    print "In do_this"

def do_that():
    print "In do_that"

dct = [do_this, do_that]
dct[0]()

如果您真的想从字符串列表中调用它们,可以使用globals():

dct = ['do_this', 'do_that']
globals()[dct[0]]()

>>> import this

功能包括 first-class objects 在Python中:

def do_this():
    pass

def do_that():
    pass

dct = [do_this, do_that]
dct[0]()  # calls do_this()

dct 当然必须是一个字符串列表,我同意 eval()

eval(dct[0] + "()")

不是很漂亮,但是在 globals() 和 getattr()

你可以用 getattr 如果它们在模块中或 globals()

dct = ['do_this', 'do_that']

getattr(my_module, dct[0])()

globals()[dct[0]]()

如果要调用的函数是模块的一部分:

import module
getattr(module, funcname_string)(*args, **kwargs)

eval() (不流行)或使用 globals()

在某个dict、类或实例中具有这些功能

def fn_a():
    pass

some_dict = {
    'fn_a': fn_a,
}

class Someclass(object):

  @classmethod
  def fn_a(cls):
    pass

  # normal instance method
  def fn_b(self):
    pass

some_instance = Someclass()

你可以: some_dict['name']() 或 getattr(some_instance, 'fn_b')() 或 getattr(Someclass, 'fn_a')()

def do_this(): pass
def do_that(): pass

dct = dict((x.__name__, x) for x in [do_this, do_that])
# dct maps function names to the function objects
# the names *don't* have to match the function name in your source:
#   dct = {"foo": do_this}
# which means user-facing names can be anything you want

dct["do_this"]()  # call do_this

使用 getattrs()

dct = ['do_this', 'do_that']


getattr(class_object, dct[0])()

inspect.getmembers(my_class, predicate=inspect.ismethod)

然后执行for循环并调用 getattr(class, methodname)

我认为使用getattr比使用globals()更适合大多数情况。

要动态调用在同一模块中定义的函数,可以这样做:

import sys

## get the reference to the current module - key trick to get the ref to same module
this = sys.modules[__name__]

def foo():
  msg="I'm called dynamically!"
  return msg

## `fname` can be taken as an input from the user
fname='foo'

## get the reference to the function from the module
fn = getattr(this, fname)

## make the function call
fn()