如何在Python中调用带有存储为字符串的变量的函数

Question

I have problem similar to describe here , but a bit more complicated. There are BeautifulSoup objects (store in list) and I want to find some other tags. The information which tags I want to find are store in strings. Ie:

a= [...] #(list of BeautifulSoup objects)
next="findNext('span')"

b=[ getattr(c,next).string for c in a]

doesn't work. What I do wrong.

Answer 1

Looks to me like what you want is:

b = [ eval("c." + next).string for c in a ]

This will call findNext('span') for each element c of the list a and form a list of the results of each findNext call in the list b .

Answer 2

Try

trees = [...] #(list of BeautifulSoup objects)
strings = [tree.findNext('span').string for tree in trees]

or, if you really must,

trees = [...] #(list of BeautifulSoup objects)
next = ('findNext', ('span',))
strings = [getattr(tree, next[0])(*(next[1])).string for tree in trees]

So I guess the next question is, what's a simple way to turn "findNext('span')" into ('findNext', ('span',)) (keeping in mind that there may be multiple arguments)?