Python--装饰器

###############################################代码1

import time
'''不是装饰器的装饰器'''

def decorator(fun):
    start = time.time()
    fun()# 这一行等同于  do_something()
    runtime = time.time()-start
    print(runtime)


def do_something():
    for i in range(10):
        pass
    print("play game")


decorator(do_something)
################################################代码2

import time


def decorator(fun):
    def wrapper():
        start = time.time()
        fun()
        runtime = time.time()-start
        print(runtime)
    return wrapper


@decorator
def do_something():
    for i in range(1000000):
        pass
    print("play game")


do_something()       #先执行@后面的函数，然后遇到“合适的机会运行do_something()函数”

#此时应该明白什么是装饰起了吧！ 明白@XXXX的作用了

##############################################################下面time2是带参数的方式

import time
def timeer(func):
    def warpper(*args,**kwargs):
        start_time=time.time()
        func(*args,**kwargs)
        stop_time=time.time()
        return 'the func run time is %s' %(stop_time-start_time)
    return warpper


@timeer   #test1=timeer(time)
def time1():
    time.sleep(1)
    print('time1')

@timeer
def time2(name,age):  #time2=time(time2)
    print(name,age)


print(time1())
print(time2('wyf',22))

==========================================================

# -*- coding: utf-8 -*-
# @Time    : 2018/9/19 14:27    L004-老男孩教育-Python14期VIP视频-18节-mp4\oldboy-8
# @Author  : wangyafeng
# @Email   : 279949848@qq.com
# @Software: PyCharm


#装饰器  本质就是函数  作用就是装饰其他函数，为其他函数添加附加功能
#一个装饰器统一为多个函数添加额外功能
# def test1():
#     logger()
#     return "test1"
#
#
# def test2():
#     return "test2"
#     logger()
#
#
# def logger():
#     print("logging")
#
# print(test1())
#装饰器原则：1不能修改被装饰的函数的源代码2不能修改被装饰函数的调用方法

# import time
#
#
# def timeer(func):
#     def warpper(*args,**kwargs):
#         start_time=time.time()
#         func()
#         stop_time=time.time()
#         print('the func run time is %s' %(stop_time-start_time))
#     return warpper
#
#
# @timeer   #test1=timeer(time)
# def time1():
#     time.sleep(3)
#     return 'time1'
#
#
# print(time1())

'''
实现装饰器的知识储备
1、函数即‘变量’
2、高阶函数
3、嵌套函数
高阶函数+嵌套函数==装饰器
'''

'''
高阶函数：1、把一个函数名当做实参传给另外一个函数2、返回值中包含函数名
'''

# #这个就是函数的嵌套
# def foo():
#     print('foo')
#     def abc():
#         print('abc')
#     abc()
#
# foo()

#多层嵌套

# def grandpa():
#     print("grandpa")
#     def dad():
#         print('dad')
#         def son():
#             print('son')
#         son()
#     dad()
# grandpa()
#

# import time
# def timeer(func):
#     def warpper(*args,**kwargs):
#         start_time=time.time()
#         func(*args,**kwargs)
#         stop_time=time.time()
#         return 'the func run time is %s' %(stop_time-start_time)
#     return warpper
#
#
# @timeer   #test1=timeer(time)
# def time1():
#     time.sleep(1)
#     print('time1')
#
# @timeer
# def time2(name,age):  #time2=time(time2)
#     print(name,age)
#
#
# print(time1())
# print(time2('wyf',22))

# import time
# def timeer(func):
#     def warpper(*args,**kwargs):
#         start_time=time.time()
#         func(*args,**kwargs)
#         stop_time=time.time()
#         return 'the func run time is %s' %(stop_time-start_time)
#     return warpper
#
#
# @timeer   #test1=timeer(time)
# def time1():
#     time.sleep(1)
#     print('time1')
#
# @timeer
# def time2(name,age):  #time2=time(time2)
#     print(name,age)
#
#
# print(time1())
# print(time2('wyf',22))


===================================================带参数的装饰器
import time
user='wyf'
pwd='abc'


def auth(auth_type):
    def out_wrapper(func):
        def wrapper(*args,**kwargs):
            if auth_type == 'local':
                username=input("name:").strip()
                password=input("password:").strip()
                if user==username and pwd==password:
                    func(*args, **kwargs)
                    print("OK")
                    return func(*args,**kwargs)
                else:
                    exit("NO")
            elif auth_type=='ldap':
                print("nonono")
        return wrapper
    return out_wrapper



def index():
    print("welcome to index page")


@auth(auth_type="local") # home = wrapper()
def home():
    print("welcome to home  page")
    return "from home"


@auth(auth_type="ldap")
def bbs():
    print("welcome to bbs  page")

index()
print(home()) #wrapper()
bbs()