python中else的用法

 

 for+else    

 1 def else1(num):
 2     for i in range(num):
 3         if(i>10):
 4             break
 5         print(i)
 6     else:
 7         print("over") #当for循环正常结束时，会执行该条语句
 8 
 9 
10 else1(5)
11 print("##"*20)
12 else1(20)
13 
14 结果：
15 
16 0
17 1
18 2
19 3
20 4
21 over
22 ########################################
23 0
24 1
25 2
26 3
27 4
28 5
29 6
30 7
31 8
32 9
33 10

 

while+else

 

 1 def else2(num):
 2     while num > 0:
 3         if(num==10):
 4             break
 5         num-=1
 6         print(num)
 7     else:
 8         print("over") #当while循环正常结束时，会执行该条语句
 9 
10 
11 else2(5)
12 print("##"*20)
13 else2(20)
14 
15 结果：
16 4
17 3
18 2
19 1
20 0
21 over
22 ########################################
23 19
24 18
25 17
26 16
27 15
28 14
29 13
30 12
31 11
32 10

 

try+else

 1 def ex(num):
 2     if(num==10):
 3         raise BaseException("BaseException!")
 4 
 5 def else3(num):
 6     try:
 7         for i in range(num):
 8             ex(i)
 9             print(i)
10     except BaseException as msg:
11         print(msg)
12     else:
13         print("over")
14     finally:
15         print("end")
16 
17 else3(5)
18 print("##"*20)
19 else3(20)
20 
21 结果：
22 0
23 1
24 2
25 3
26 4
27 over
28 end
29 ########################################
30 0
31 1
32 2
33 3
34 4
35 5
36 6
37 7
38 8
39 9
40 BaseException!
41 end

 

posted @ 2019-11-24 09:32  月色深潭  阅读(1343)  评论(0)  编辑  收藏  举报