Python 异常处理

1，简单异常处理

try:
    date["name"]
    names[3]
except (IndexError, KeyError) as e:
    print('检测IndexError/KeyError异常', e)
except Exception as e:
    print('检测所有异常', e)
else:
    print('一切正常')
finally:
    print('有错无措，都执行')

2，自定义异常处理

# 自定义异常类，继承Exception
class ElvaException(Exception):
    def __init__(self, msg):
        self.message = msg

    def __str__(self):
        return '测试测试'
        # return self.message
try:
    raise ElvaException('数据库连接错误')  # raise调用自己定义异常
except ElvaException as e:
    print(e)