python学习随笔之流程控制---while

死循环:

1 #!/usr/bin/python
2 while 1:
3     print "hello"

设置条件跳出循环:

1 #!/usr/bin/python
2 x = ""              #定义x为空字符,如果不定义会出现语法错误
3 while x != "q":#如果x不等于q为真,则循环,如果x不等于q为假,即x=q为真,则跳出循环,执行"ending" 
4     print "hello"
5     x = raw_input("please input something ,q for quit: ")
6 else:
7     print "ending"

上述方法使用q退出,也可以使用回车退出

1 #!/usr/bin/python
2 x = ""             
3 while x != "q":4     print "hello"
5     x = raw_input("please input something ,q for quit: ")
6     if not x:
7         break
8 if x == c:
9 continue
10 print "#"*50
11 else: 12 print "ending"

跳出循环则不显示ending

continue用法与for一样:

 1 #!/usr/bin/python
 2 x = ""
 3 while x != "q":
 4     print "hello"
 5     x = raw_input("please input something ,q for quit: ")
 6     if not x:
 7         break
 8     if x == "c":
 9        continue
10     print "#"*50
11 else:
12     print "ending"

当输入a时:

hello

###################

当输入c时:

hello

无#显示,因为continue

posted @ 2017-02-16 16:35  皮蛋solo粥  阅读(180)  评论(0编辑  收藏  举报