今日作业
题目：
让用户输入用户名和密码
校验用户名是否存在
用户名存在后校验密码是否正确，若正确打印“登录成功”，
否则打印“用户名或密码错误”，并让用户重新输入
用户密码输入错误超过三次退出循环
hw.py
#模拟后台用户信息数据库
name_dict = {'John Wick':'2014','Ethan Hunt':'2000','Bourne':'2002'}
# 登录信息验证
def sign_in():
i = 0
while True:
name = input('请输入用户名:')
pwd = input('请输入密码:')
#校验用户名是否存在
if(name in name_dict.keys() and pwd == name_dict.get(name)):
print('登陆成功!')
break
else:
if(i < 2):
print('用户名或密码错误，请重新输入')
i = i + 1
elif(i == 2):
print('您已输错三次，请明天再试')
break
sign_in()
课程回顾
主要内容：
- 数据类型剩余的内置方法（list,dict,tuple,set)
- 字符编码
- 文件处理
- 函数基础
list方法
insert()插入
list1 = ['ktan',18,'male',3.0,9,'光之国']
list1.insert(2,'Young OG')
print(list1)
count()
list1.append('ktan')
print(list1.count('ktan'))
index()
print(list1.index('光之国'),'---光之国')
copy()
list1.append(['Q'])
print(list1)
- 浅拷贝
list2 = list1.copy()
- 深拷贝
from copy import deepcopy
list4 = deepcopy(list1)
list3 = list1
list1.append('RUChange')
print(list2,'Change?')
print(list3,'Change?')
print(list4,'Change?')
list1[list1.index(['Q'])].append('M')
print(list2,'copy after model list change')
print(list3,'= after model list change')
print(list4,'deepcopy after model list change')
clear()
list1.clear()
print(list1)
print(list2)
list3 = list1
print(list3)
list1.append('Real OG')
print(list1,list3)
extends
list1 = [1,2,3]
list2 = [4,5,6]
list1.extend(list2)
print(list1)
sort()
list3 = [1,2,4,7,32,833,55]
# default ascending
list3.sort()
print(list3)
# descending
list3.sort(reverse = True)
print(list3)
字典内置方法
1.get/set value by key
dict1 = {'name':'DeathGum','age':20,'school':'Unkown'}
# get()
print(dict1.get('school','xxx'))
2.length of dict
print(len(dict1))
3.成员运算
print('name' in dict1) # True
print('sal' in dict1) # False
print('sal' not in dict1) # True
4.delete
name = dict1.pop('name')
print(dict1)
print(name)
dict1.popitem() # 随机删除某个item
print(dict1)
5.keys values items
dict1 = {'name':'DeathGum','age':20,'school':'Unkown'}
print(dict1.keys())
print(dict1.values())
print(dict1.items())
6.loop
for key in dict1:
print(key)
7.update
print(dict1)
dict2 = {"work": "student"}
# 把dict2加到dict1字典中
dict1.update(dict2)
print(dict1)
元祖和集合
# tuple1 = (1, 2, 3, 4, 5, 6)
# print(tuple1)
# # 优先掌握
# # 1.按索引取值
# print(tuple1[2])
#
# # 2.切片(顾头不顾尾)
# print(tuple1[0:6]) # (1, 2, 3, 4, 5, 6)
#
# # 步长
# print(tuple1[0:6:2]) # (1, 3, 5)
#
# # 3.长度
# print(len(tuple1)) # 6
#
# # 4.成员运算 in 和 not in
# print(1 in tuple1) # True
# print(1 not in tuple1) # False
#
# # 5.循环
# for line in tuple1:
# print(line)
# 三 集合类型(一般用于去重)
# 在{}以逗号隔开，可存放多个值，但集合会自带默认去重功能。
# set1 = {1, 2, 3, 4, 2, 1, 3, 4}
# print(set1)
#
# # 集合是无需的
# set1 = set()
# set2 = {}
# print(set1)
# print(set2)
#
# set2['name'] = 'tank'
# print(type(set2))
文件操作
import requests
# # 文件读写基本操作
# # 对文本进行操作
# # open ('file name',mode = 'wt',encoding='utf-8')
# f = open('/Users/nadia/Code/Python/test.txt',mode='wt',encoding='utf-8')
# f.write('aifhjsdvlafsddkfj')
# f.close
# f = open('/Users/nadia/Code/Python/test.txt',mode='r',encoding='utf-8')
# print(f.read())
# # append mode
# f = open('/Users/nadia/Code/Python/test.txt',mode='a',encoding='utf-8')
# f.write('\nfghjk')
# f.close
# #结合网络爬虫进行图片读写
str1 = 'https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1560334128444&di=2258333ac43a3451265b9ef0081e6455&imgtype=0&src=http%3A%2F%2Fimg.tw.mm52.com%2Ft%2Ftakeshi_kitano%2Ftakeshi_kitano_0080_128px.jpg'
r = requests.get(str1)
with open('nmb.jpg',mode='wb') as f:
f.write(r.content)
# 视频文件读写
# with open('tianyan_sys.mp4','rb')as f,open('tianyan_sys_copy.mp4','wb')as w:
# for line in f:
# f.read(line)
# w.write(line)
# f.close()
# w.close()
基本函数
def fib(n):
result = []
a,b = 0,1
while a result.append(a) a,b = b,a+b return result f = fib print(f(100)) def register(): while True: user = input('请输入用户名:').strip() pwd = input('请输入密码：').strip() re_pwd = input('请确认密码：').strip() if pwd == re_pwd: # 格式字符串的三种方式 ''' user_info = '用户名:%s , 密码:%s',user,pwd user_info = '用户名:{}, 密码:{}'.formate(user,pwd) ''' user_info = f'用户名:{user},密码:{pwd}' with open(f'{user}.txt','w',encoding='utf-8')as f: f.write(user_info) break else: print('两次密码不一致，请重新输入') #定义阶段和调用阶段未定义函数语句在interpreter中报错与不报错 register()