装饰器(二)

装饰器(二)

1.有参装饰器

在装饰器的基础上在套一层

lodic_dic = {"username":None,"flag":False}
msg = '''
QQ
微信
抖音
邮箱
请输入你要选择登陆的app:
'''
chose = input(msg).upper()

def auth(argv):
    def wrapper(func):
        def inner(*args,**kwargs):
            if logic_dic["flag"]:
                func(*args,**kwargs)
            else:
                if argy == "QQ":
                    print("欢迎登陆QQ")
                    user = input("username:")
                    pwd = input("password:")
                    if user =="alex",and pwd == "alex123":
                        logic_dic["flag"] = True
                        logic_dic["username"] = user
                        func(*args,**kwargs)
                    else:
                        print("用户名或密码错误")
                elif argv == "微信":
                    print("欢迎登陆微信")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "wusir" and pwd =="wusir123":
                        logic_dic["flag"] = True
                        logic_dic["username"] = user
                        func(*args,**kwargs)
                    else:
                        print("用户名或密码错误")
                elif argv == "抖音":
                    print("来了,老弟")
                    user = input("username:")
                    pwd = input("password:")
                    if user == "alex" and pwd == "lexa":
                        logic_dic["flag"] = True
                        logic_dic["username"] = user
                        func(*args,**kwargs)
                    else:
                        print("用户名或密码错误")
                else:
                    print("欢迎登陆邮箱")
                    user = input("username:")
                    pwd = input("password:")
                    if user== "alex@qq.com" and pwd =="ale":
                        logic_dic["flag"] = True
                        logic_dic["username"] = user
                        func(*args,**kwargs)
                    else:
                        print("用户名或密码错误")
		return inner
    return wrapper
@auth("QQ")
def foo():
    print("这是一个被装饰的函数")

    
    
@auth(chose) 相当于以下两行代码的解构
wrapper = auth(chose)
foo = wrapper(foo)

2.多个装饰器装饰一个函数

被装饰的函数正上方有多个装饰器,先执行离被装饰函数最近的装饰器
def wrapper1(func):
    def inner1(*args,**kwargs):
        print(1)
        func(*args,**kwargs)
        print(11)
    return inner1

def wrapper2(func):
    def inner2(*args,**kwargs):
        print(2)
        func(*args,**kwargs)
        print(22)
    return inner2

def wrapper3(func):
    def inner3(*args,**kwargs):
        print(3)
        func(*args,**kwargs)
        print(33)
    return inner3

@wrapper1
@wrapper2
@wrapper3
def foo():
    print("这是一个被装饰的函数")
foo()

解析:
foo = wrapper3(foo)    # foo = inner3
foo = wrapper2(foo)    # foo = wrapper2(inner3) foo==inner2
foo = wrapper1(foo)    # foo = wrapper1(inner2)

# 1 2 3 这是一个被装饰的函数 3 2 1
小技巧:进入装饰器从下往上,走到最后一个装饰器执行被装饰的函数,退出装饰器从下往上走