如何动态选择一个方法调用? [英] How to dynamically select a method call?

问题描述

我有一个类似的代码:

if command == "print":
     foo_obj.print()

if command == "install":
     foo_obj.install()

if command == "remove":
     foo_obj.remove()

command 是一个字符串(我通过解析命令行参数来定义它，但这已经超出了重点).有没有办法用类似的东西替换上面的代码?

command is a string (I define it by parsing command line arguments, but that's beyond the point). Is there a way to replace the above chunck of code with something similar to this?

foo_obj.function(command)

对于重新录制的内容，我使用的是 Python 2.7

For the recored I'm using Python 2.7

推荐答案

核心功能可能为:

fn = getattr(foo_obj, str_command, None)
if callable(fn):
    fn()

当然，您应该只允许某些方法:

Of course, you should allow only certain methods:

str_command = ...

#Double-check: only allowed methods and foo_obj must have it!
allowed_commands = ['print', 'install', 'remove']
assert str_command in allowed_commands, "Command '%s' is not allowed"%str_command

fn = getattr(foo_obj, str_command, None)
assert callable(fn), "Command '%s' is invalid"%str_command

#Ok, call it!
fn()    

这篇关于如何动态选择一个方法调用?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！