python_异常处理

 1 a = [1,2,3]
 2 d = {}
 3 #例子1：
 4 #判断key异常
 5 try:
 6     d[‘name‘]
 7 except KeyError as e:
 8     print("字典key不存在",e)
 9 else:
10     print(‘正常运行‘)
11 finally:
12     print("有没有异常都走这里")
13 
14 #例子2
15 #判断下标异常
16 try:
17     a[3]
18 except IndexError as e:
19     print(‘下标越界‘)
20 else:
21     print(‘正常运行‘)
22 finally:
23     print(‘有没有异常都走这里‘)
24 
25 # 例子3
26 #捕捉全部异常
27 try:
28     a[3]
29     d[‘name‘]
30 except Exception as e:
31     print(‘出现异常了‘)
32 finally:
33     print(‘有没有异常都走这里‘)
34 
35 #raise主动抛出异常
36 price = input(‘price:‘)
37 if not price.isdigit():
38     raise Exception(‘价格错误‘)