1、编写课上讲解的有参装饰器准备明天默写
def auth(db_type):
# db_type= 'file'
def outer(func):
def wrapper(*args,**kwargs):
user = input('name').strip()
pwd = input('pwd').strip()
if db_type == 'file':
print('我是基于文件登录的')
if user == 'egon' and pwd == '123':
res = func(*args,**kwargs)
return res
else:
print('登陆失败')
elif db_type == 'msql':
print('我是基于数据库msql登录的')
elif db_type == 'ldap':
print('我是基于ldap登录的')
else:
print('我不支持此类型')
return wrapper
return outer
@auth('file') # outer = auth('file')
def index(x,y):
print(x,y)
index(1,2)
@auth('msql')
def f1(x,y):
print(x,y)
# 总结:有参装饰器的模板
# 有参装饰器模板
def 有参装饰器(x,y,z):
def outter(func):
def wrapper(*args, **kwargs):
res = func(*args, **kwargs)
return res
return wrapper
return outter
@有参装饰器(1,y=2,z=3)
def 被装饰对象():
pass
2:还记得我们用函数对象的概念,制作一个函数字典的操作吗,来来来,我们有更高大上的做法,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_fun = {}
# 将每个功能添加到字典中的功能
def num(key):
def outer(func):
def wrapper(*args,**kwargs):
res = func(*args,**kwargs)
dic_fun[key] = (func.__doc__,func)
return res
return wrapper
return outer
# 登录功能
@num(0)
def login():
"""登录"""
print('我是登录功能')
login()
# 洗碗功能
@num(1)
def wash():
"""洗碗"""
print('欢迎当劳动小能手❤')
wash()
# 跑步功能
@num(2)
def run():
"""跑步"""
print('欢迎体验马拉松障碍赛❤')
run()
for i,v in dic_fun.items():
print(i,v)
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
注意:时间格式的获取
import time
time.strftime('%Y-%m-%d %X')
import time
def file(src):
def add_time(func):
def wrapper(*args,**kwargs):
res = func(*args,**kwargs)
with open(src,'a',encoding='utf-8') as f:
f.write(f'{res}\n')
return res
return wrapper
return add_time
src = input(r'请输入文件路径')
@file(src)
def current_time():
res = time.strftime('%Y-%m-%d %X')
print(res)
return res
current_time()
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
# 1 字符串
my_str = 'hello'
# 1 将可迭代对象转成迭代器
my_str_iteration = my_str.__iter__()
# 2 while循环取出值
while True:
try:
print(my_str_iteration.__next__())
except StopIteration:
break
# 2 列表
my_list = [1,2,3]
# 1 将可迭代对象转成迭代器
my_list_iteration = my_list.__iter__()
# 2 while循环取出值
while True:
try:
print(my_list_iteration.__next__())
except StopIteration:
break
# 3 元组
my_tup = (1,2,3)
# 1 将可迭代对象转成迭代器
my_tup_iteration = my_list.__iter__()
# 2 while循环取出值
while True:
try:
print(my_tup_iteration.__next__())
except StopIteration:
break
# 4 字典
dic = {'a':1,'b':2}
# 1 转换成迭代器
dic_iteration = dic.__iter__()
# while 循环取值
while True:
try:
print(dic_iteration.__next__())
except StopIteration:
break
# 5 集合
my_set = (1,2,3)
# 1 将可迭代对象转成迭代器
my_set_iteration = my_list.__iter__()
# 2 while循环取出值
while True:
try:
print(my_set_iteration.__next__())
except StopIteration:
break
# 6 文件对象
with open('time','r',encoding='utf-8') as f:
while True:
try:
print(f.__next__())
except StopIteration:
break
5、自定义迭代器实现range功能
def my_range(start,stop,step):
while start < stop:
yield start
start += step
res = my_range(1,10,2)
# 此时res是一个自定义的迭代器,不会执行函数体代码
while True:
try:
print(next(res))
except StopIteration:
break
for i in range(1,10,2):
print(i)