5. 循环

1. while 循环

while condition:

statement1

statement2

else

statement3

statement4

2. for 循环

for target in sequences:

statement

else:

statement2

sequences包括：

list, tuple, strings, files

(1) strings

for string in "Like": 

 print(string)

(2) list:

lst = [1, 3, 5, "Like", "test", 12.5, 32.6] 

for value in lst: 

 print(value) 

else:

 print("Out loop")

(3) list 2:

str1 = "I Like Like" 

lst = list(str1) 

for value in lst: 

 print(value) 

else: 

 print("Out loop")

(4) tuples

tuple = (1, 2, 3, 4, 5) 

for tup in tuple: 

 print(tup) 

else: 

 print("Out loop")

(5) 文件

file = open("D:/test/test.txt") 

for content in file.readlines(): 

 print(content) 

else: 

 print("End read")

(6) 循环写入文件（文件拷贝）

file = open("D:/test/test.txt", "r") 

for content in file.readlines(): 

 open("D:/test/test2.txt", "a+").write(content) 

else: 

 print("End read")

3. 额外知识

listNum = range(1, 25)

产生1 - 24的数组