Question

我想使用列表中的项目作为字典键来查找嵌套字典中的值。

例如，给出以下列表：

keys = ['first', 'second', 'third']

我想这样做：

result = dictionary[keys[0]][keys[1]][keys[2]]

这相当于：

result = dictionary['first']['second']['third']

但我不知道预先在keys列表中有多少项目（除了它总是至少有1个）。

Answer 1

迭代地进入子区域。

result = dictionary
for key in keys:
  result = result[key]
print(result)

Answer 2

一个简单的for循环可以工作：

result = dictionary[keys[0]]  # Access the first level (which is always there)
for k in keys[1:]:            # Step down through any remaining levels
    result = result[k]

演示：

>>> dictionary = {'first': {'second': {'third': 123}}}
>>> keys = ['first', 'second', 'third']
>>> result = dictionary[keys[0]]
>>> for k in keys[1:]:
...     result = result[k]
...
>>> result
123
>>>

使用列表项作为嵌套字典的键

2 个答案: