【python 】装饰器 （多个参数的函数，带参数的装饰器）【转】

最简单的模板是这样的

#-*-coding:utf-8-*-

def outer(func):
    def inner():
        print 'before'
        func()
        print 'after'
        # return r
    return inner
'''
def outer_1(func):
    def inner():
        print 'before 11'
        func()
        print 'after 22'
        # return r
    return inner

@outer_1
'''
@outer
def F1():
    print 'test'

if __name__ == '__main__':
    F1()
'''
运行结果
before
test
after
[Finished in 0.1s]
'''

函数带多个参数，装饰器对应修改以适合多种情况

# -*- coding: utf-8 -*-

from time import ctime
from time import sleep

def ftfunc(func):
    def timef(*s,**gs):
        print "[%s] %s() called" % (ctime(),func.__name__)
        return func(*s,**gs)
    return timef

@ftfunc
def foo(*s,**gs):
    print(s)
    print(gs)

if __name__ == '__main__':
    foo()
    foo(1)
    foo(1,2)
    foo(1,2,3)
    stu = {'name' : 'alam' ,'age' :12}
    foo(1,2,3,**stu)
'''
运行结果
[Wed Jun 14 15:49:55 2017] foo() called
()
{}
[Wed Jun 14 15:49:55 2017] foo() called
(1,)
{}
[Wed Jun 14 15:49:55 2017] foo() called
(1, 2)
{}
[Wed Jun 14 15:49:55 2017] foo() called
(1, 2, 3)
{}
[Wed Jun 14 15:49:55 2017] foo() called
(1, 2, 3)
{'age': 12, 'name': 'alam'}
[Finished in 0.1s]

'''

函数带多个参数，装饰器也带多个参数

# -*- coding: utf-8 -*-

def decrator(*dargs, **dkargs):
    def wrapper(func):
        def _wrapper(*args, **kargs):
            print "decrator param:", dargs, dkargs
            print "function param:", args, kargs
            return func(*args, **kargs)
        return _wrapper
    return wrapper

@decrator(1, a=2)
def foo(x, y=0):
    print "foo", x, y


if __name__ == '__main__':
    foo(3, 4)

'''
执行结果
decrator param: (1,) {'a': 2}
function param: (3, 4) {}
foo 3 4
[Finished in 0.1s]
'''

函数带多个参数，装饰器能转换参数类型

# -*- coding: utf-8 -*-

def validate(**vkargs):
    def decorator(func):
        def wrapper(**kargs):
            for key in vkargs:
                # 根据vkargs中的参数的类型对kargs的参数进行类型转换
                kargs[key] = vkargs[key](kargs[key])
            return func(**kargs)
        return wrapper
    return decorator


@validate(x=int, y=float, z=float)
def move(x, y, z):
    print "move %d (%0.2f, %0.2f)"%(x, y, z)



if __name__ == '__main__':
    move(x="1", y="0.2", z="0.3")
'''
运行结果
move 1 (0.20, 0.30)
[Finished in 0.2s]
'''

一个简单的例子，登录页面

# -*- coding: utf-8 -*-

#模拟网站登陆访问认证

name = 'abc'
password='123'

def certi(model):#装饰器
    def outr(fun):#装饰器加参数需要多加一层嵌套
        def login(*args,**kwargs):#为了兼容各类函数参数，添加 *args,**kwargs 不固定参数
            if model=='password':
                print('enter password')
                user_name = raw_input('user_name ').strip()
                paswd=raw_input('password ').strip()
                if user_name==name and paswd==password:
                    print('pass')
                    return fun(*args,**kwargs)
                else:
                    print('error ')
                    exit()
            elif model=='lamp':
                print('this is lamp')
                return fun(*args,**kwargs)
            else:
                print('error')
        return login
    return outr


def indxe():
    print('home page !!')

@certi(model='password')
def user():
    print('user page !!')

@certi(model='lamp')
def bbs(name):
    print('bbs %s!!'%name)



if __name__ == '__main__':
    indxe()
    user()
    bbs(name='yjj')
'''
运行结果
home page !!
enter password
user_name abc
password 123
pass
user page !!
this is lamp
bbs yjj!!
'''