How to dynamically call a method in python?

Question

I would like to call an object method dynamically.

The variable "MethodWanted" contains the method I want to execute, the variable "ObjectToApply" contains the object. My code so far is:

MethodWanted=".children()"

print eval(str(ObjectToApply)+MethodWanted)

But I get the following error:

exception executing script
  File "<string>", line 1
    <pos 164243664 childIndex: 6 lvl: 5>.children()
    ^
SyntaxError: invalid syntax

I also tried without str() wrapping the object, but then I get a "cant use + with str and object types" error.

When not dynamically, I can just execute this code to get the desired result:

ObjectToApply.children()

How to do that dynamically?

Answer 1

Methods are just attributes, so use getattr() to retrieve one dynamically:

MethodWanted = 'children'

getattr(ObjectToApply, MethodWanted)()

Note that the method name is children, not .children(). Don't confuse syntax with the name here. getattr() returns just the method object, you still need to call it (jusing ()).