1、列表定义

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表存储，类似数组

2、列表的操作

(1)切片

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表存储，类似数组

print(names[1],names[3]) #取值，1、3代表下标，从左到右的位置

执行结果：

Guyun Xuliangchen

print(names[1:3]) #切片,顾头不顾尾取[1]、[2]的值

print(names[0:3]) #切片

print(names[:3]) #等同于0:3，从下标0到3

print(names[-1]) #切片,取倒数第一个值

print(names[-2]) #取倒数第二个值

print(names[-2:]) #取最后两个值

(2)增加--append：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names.append("LeiHaidong") #追加到最后

print(names)

执行结果：

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen', 'LeiHaidong']

(3)修改--insert：

names.insert(1,"Chenronghua") #数据插入，插在哪个位置前面就写这个元素的下标,如插在Guyun前面

names.insert(3,"Xinzhiyu") #插在Guyun后面

print(names)

执行结果：

['ZhangYang', 'Chenronghua', 'Guyun', 'Xinzhiyu', 'Xiangpeng', 'Xuliangchen', 'LeiHaidong']

(4)查询--index：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

print(names)

print(names.index("Xiangpeng")) #查出Xiangpeng的位置

print(names[names.index("Xiangpeng")]) #获取下标内容

执行结果：

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

2

Xiangpeng

(5)统计--count：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

print("count-->",names.count("ZhangYang"))

执行结果：

count--> 1

(6)反转--reverse:

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names.reverse()

print(names)

执行结果：

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

reverse--> ['Xuliangchen', 'Xiangpeng', 'Guyun', 'ZhangYang']

(7)扩展--extend：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names2 = [1,2,3,4]

print(names)

names.extend(names2)

print("extend-->",names)

执行结果：

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

extend--> ['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen', 1, 2, 3, 4]

(8)排序--sort：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names.sort()

print(names)

执行结果：

['Guyun', 'Xiangpeng', 'Xuliangchen', 'ZhangYang']

(9)清除--clear：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names.clear()

print(names)

执行结果：

[]

(10)复制--copy：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]

names2 = names.copy()

print(names)

print(names2)

names[1] = "古云" #更改Guyun,可以看到names2中并没有修改

print("names-->",names)

print("names2-->",names2)

执行结果：

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

names--> ['ZhangYang', '古云', 'Xiangpeng', 'Xuliangchen']

names2--> ['ZhangYang', 'Guyun', 'Xiangpeng', 'Xuliangchen']

(11)列表嵌套复制--copy.deepcopy：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"]

names2 = names.copy()

print(names)

print(names2)

names[1] = "古云"

names[2][0] = "ALEX" #更改列表中的alex为ALEX,可以看到names2中也相应更改

print("names-->",names)

print("names2-->",names2)

执行结果：

['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']

['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']

names--> ['ZhangYang', '古云', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']

names2--> ['ZhangYang', 'Guyun', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']

★★★★注意：这里的的copy只会拷贝第一层，列表中包含列表，其中列表是指向存放列表的内存地址，所以在更改列表中的元素时，拷贝的部分也会相应地更改。

为了实现深入拷贝，可以导入copy模块：

import copy

names2 = copy.deepcopy(names)

print(names)

print(names2)

names[1] = "古云"

names[2][0] = "ALEX"

print("names-->",names)

print("names2-->",names2)

执行结果：

['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']

['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']

names--> ['ZhangYang', '古云', ['ALEX', 'jack'], 'Xiangpeng', 'Xuliangchen']

names2--> ['ZhangYang', 'Guyun', ['alex', 'jack'], 'Xiangpeng', 'Xuliangchen']

可以看到拷贝是完全克隆过来的，但是生产过程中一般不会使用，拷贝多一份数据，等于多占据了一份内存空间。

(12)for循环列表：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"]

for i in names:

print(i)

执行结果：

ZhangYang

Guyun

['alex', 'jack']

Xiangpeng

Xuliangchen

(13)步长切片：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"]

print(names[0:-1:2]) #打印第一个到最后一个，步长为2

执行结果：

['ZhangYang', ['alex', 'jack']]

3、程序练习

程序：购物车程序

需求:

启动程序后，让用户输入工资，然后打印商品列表

允许用户根据商品编号购买商品

用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒

可随时退出，退出时，打印已购买商品和余额

#!/usr/bin/python

# _*_ coding:utf-8 _*_

# Aothr: Kim

goods_list = [

['Iphone',5800],

['Mac pro',9800],

['Bike',800],

['Watch',10600],

['Coffee',31],

['Alex Python',120]

]

shopping_list = [] #此列表为空当做购物车使用

salary = input("Please input your salary:")

if salary.isdigit():

salary = int(salary)

while True:

for index,item in enumerate(goods_list): #enumerate可以取出列表的下标和内容

print(index,item)

user_choice = input("请选择你需要的商品编号：")

if user_choice.isdigit():

user_choice = int(user_choice)

if user_choice < len(goods_list) and user_choice >= 0: #len可以取出列表的长度

g_item = goods_list[user_choice]

if g_item[1] <= salary:

shopping_list.append(g_item)

salary -= g_item[1]

print("已成功添加商品%s到购物车，当前余额为\033[31;1m%s\033[0m" % (g_item, salary))

else:

print("您的余额为%s，无法购买此商品，请充值！"%salary)

else:

print("您的选择的商品编号%s有误，请重新选择:"%user_choice)

elif user_choice == 'q':

print('------goods list------')

for p in shopping_list:

print(p)

print("您当前余额为%s"%salary)

exit()

else:

print("您的输入有误，请输入正确的商品编号！")