python异常处理

　　　　

names = ['alex','jack']
data = {}
try:
    data['name']
except KeyError as e:
    print("没有这个key",e)
except Exception as e:
    print("未知错误", e)
else:
    print("一切正常")
finally:
    print("不管有没有错，都执行")

 

自定义异常：

　　raise触发异常

　　　　

class RogerException(Exception):
    def __init__(self,msg):
        self.message = msg

try:
    raise RogerException('脑子短路')
except RogerException as e:
    print(e)