def outter(db_type):
def auth(func):
def wrapper(*args, **kwargs):
name = input('请输入姓名; ')
pwd = input('请输入密码： ')
if db_type == 'file':
with open('pwd.txt', 'rt', encoding='utf-8')as file:
for line in file:
user_name, password = line.strip().split(':')
if name == user_name and pwd == password:
print('登录成功！')
res = func(*args, **kwargs)
return res
else:
print('登录失败！')
elif db_type == 'MySQL':
print('数据库我还不会')
elif db_type == 'ldap':
print('这个我也还不会')
else:
print('db_type不持支该操作')
return wrapper
return auth
2.在文件开头声明一个空字典，然后在每个函数前加上装饰器，完成自动添加到字典的操作
dic={}
key=0
def add_dic(func):
def warpper(*args,**kwargs):
global key
dic[key]=func
key+=1
return warpper()
3、 编写日志装饰器，实现功能如：一旦函数f1执行，则将消息2017-07-21 11:12:11 f1 run写入到日志文件中，日志文件路径可以指定
import time
def outter(file_path):
def log(func):
def wrapper(*args,**kwargs):
res=func(*args,**kwargs)
res = time.strftime('%Y-%m-%d %X')
with open(file_path,'a',encoding='utf-8')as file:
file.write(res)
return wrapper
return log
('log.txt')
def f1(x,y):
print('hello %s %s'%(x,y))
f1(1,2)
4、基于迭代器的方式，用while循环迭代取值字符串、列表、元组、字典、集合、文件对象
x='hello'
res1=x.__iter__()
while 1:
try:
print(res1.__next__())
except StopIteration:
break
l=[1,2,3,4,5]
res2=l.__iter__()
while 1:
try:
print(res2.__next__())
except StopIteration:
break
set1={1,2,3,4,5}
res3=set1.__iter__()
while 1:
try:
print(res3.__next__())
except StopIteration:
break
dic1={'name':'jake','age':18}
res4=dic1.__iter__()
while 1:
try:
print(res4.__next__())
except StopIteration:
break
tup1=(1,2,3,4,5)
res5=tup1.__iter__()
while 1:
try:
print(res5.__next__())
except StopIteration:
break
with open('a.txt','r',encoding='utf-8')as file:
while 1:
try:
print(file.__next__())
except StopIteration:
break
5、自定义迭代器实现range功能
def my_raneg(start,end,step):
while start<end:
yield start
start+=step
num=my_raneg(1,10,2)
print(next(num))
print(next(num))
print(next(num))
print(next(num))