python3 之装饰器学习

import time


def logger(func):
    def wrapper(*args,**kw):
        print('我准备开始计算；{} 函数了:'.format(func.__name__))
        func(*args,**kw)

        print('啊哈，我计算完啦。给自己加个鸡腿！！')
    return wrapper

@logger
def add(x,y):
    print('{} + {} = {}'.format(x, y, x+y))

add(x= 200,y =50)



def timer(func):
    def wrapper(*args,**kw):
        t1 = time.time()
        func(*args,**kw)
        t2 =time.time()
        cost_time =t2-t1
        print("花费时间：{}秒".format(cost_time))
    return wrapper

@timer
def want_sleep(sleep_time):
    time.sleep(sleep_time)



want_sleep(10)




def say_hello(contry):
    def wrapper(func):
        def deco(*args,**kw):
            if contry =='china':
                print("你好")
            elif contry == "american":
                print('hello .')
            else:
                return
            func(*args,**kw)
        return deco
    return wrapper


@say_hello('american')
def american():
    print("I am from American")
@say_hello('china')
def chinese():
    print("我来自中国")


american()
print('-----------')
chinese()

　　

最近因为在某公众号上看到装饰器用于测试异常处理，所以就学习了一下装饰器