在 Python 中处理 KeyError

Question

我如何使用 if 处理KeyError ？ 根据错误，以不同的方式处理错误。

speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes']['team_normal']
speed_uhc_solo = counts_stats['games']['SPEED_UHC']['modes']['solo_normal']

我想要的是，如果字典中不存在键team_normal ，则将我选择的值分配给该键。

但是当key team_normal存在时，只分配key值。

Answer 1

这应该这样做：

d = { "team_solo": True}

if "team_normal" in d:
    print("I found team_normal in d!")

if "team_solo" in d:
    print("I found team_solo in d!")

Answer 2

只需检查密钥是否存在：

if 'team_normal' not in counts_stats['games']['SPEED_UHC']['modes'].keys():
    speed_uhc_team = my_choice_value
    
else:
    speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes']['team_normal']

Answer 3

try: speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes']['team_normal'] except KeyError: speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes']['other_key']

Answer 4

如果只有最后一个键可以不存在，您可以使用get ：

speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes'].get('team_normal',
                                                                 default_value)

如果你想挂起任何关键错误，你应该使用一个 try 块：

try:
    speed_uhc_team = counts_stats['games']['SPEED_UHC']['modes']['team_normal']
except KeyError:
    speed_uhc_team = default_value