break和continue在while循环中

 

continue: 返回到循环开头，并根据条件测试结果决定是否继续执行循环。

例：

n=0
while n<10:
    n+=1
    if n%2==0:
        continue  #返回到循环开头
    print(n)

运行结果：

====================== RESTART: D:/python学习/continue.py ======================
1
3
5
7
9
>>> 

 break：用于控制程序的流程，可使用它来控制哪些代码行将执行，从而让程序按你的要求执行。（在循环中都可使用break语句，立即退出不再执行余下的代码）

例：

 

prompt='\nPlease enter the name of a city you have visited:'
prompt+='\n(Enter "quit" when you are finished.'
while True:
    city=input(prompt)
    if city=="quit":
        break
    else:
        print("I'd love to go to "+city.title()+"!")  #title() 方法返回"标题化"的字符串,就是说所有单词都是以大写开始，其余字母均为小写

 

运行结果：

>>> 
======================= RESTART: D:/python学习/break.py =======================

Please enter the name of a city you have visited:
(Enter "quit" when you are finished.beigjing
I'd love to go to Beigjing!

Please enter the name of a city you have visited:
(Enter "quit" when you are finished.广州
I'd love to go to 广州!

Please enter the name of a city you have visited:
(Enter "quit" when you are finished.quit
>>>