python基础之函数进阶

Posted 2020-08-09

装饰器

s1.py
def outer(func):
    def inner():
        print("before")
        func()
        print("after")
    return inner

@outer
def f1():
    print("F1")

s2.py
import s1
s1.f1()

#输出

before

F1

after

 

装饰器格式

@+函数

功能

　　1 自动执行outer函数并且将下面的函数名f1当作参数传递

　　2 将outer函数的返回值，重新赋值给f1

　　f1重新赋值成装饰器函数的内存函数

 

f1等于inner这个函数

 

装饰器之返回值

def outer(func):
    def inner():
        print("before")
        r = func()
        print("after")
        return r
    return inner

@outer
def f1():
    print("F1")
    return "dada"

import zsq
ret = zsq.f1()
print(‘fanhuizhi‘,ret)

 #输出

before
F1
after
fanhuizhi dada

装饰器之参数

def outer(func):
    def inner(a):
        print("before")
        r = func(a)
        print("after")
        return r
    return inner

@outer
def f1(arg):
    print(arg)
    return "dada"

import zsq
ret = zsq.f1(‘aaa‘)
print(‘fanhuizhi‘,ret)

#输出

before
aaa
after
fanhuizhi dada

def outer(func):
    def inner(*args,**kwargs):
        print("before")
        r = func(*args,**kwargs)
        print("after")
        return r
    return inner

@outer
def f1(arg):
    print(arg)
    return "dada"
@outer
def f2(a1,a2):
    print(a1)
    print(a2)

import zsq
ret = zsq.f1(‘aaa‘)
print(‘fanhuizhi‘,ret)
zsq.f2(11,22)

#输出 

before
aaa
after
fanhuizhi dada
before
11
22
after