最简单的模板是这样的
1 #-*-coding:utf-8-*-
2
3 def outer(func):
4 def inner():
5 print 'before'
6 func()
7 print 'after'
8 # return r
9 return inner
10 '''
11 def outer_1(func):
12 def inner():
13 print 'before 11'
14 func()
15 print 'after 22'
16 # return r
17 return inner
18
19 @outer_1
20 '''
21 @outer
22 def F1():
23 print 'test'
24
25 if __name__ == '__main__':
26 F1()
27 '''
28 运行结果
29 before
30 test
31 after
32 [Finished in 0.1s]
33 '''
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
1 # -*- coding: utf-8 -*-
2
3 def validate(**vkargs):
4 def decorator(func):
5 def wrapper(**kargs):
6 for key in vkargs:
7 # 根据vkargs中的参数的类型对kargs的参数进行类型转换
8 kargs[key] = vkargs[key](kargs[key])
9 return func(**kargs)
10 return wrapper
11 return decorator
12
13
14 @validate(x=int, y=float, z=float)
15 def move(x, y, z):
16 print "move %d (%0.2f, %0.2f)"%(x, y, z)
17
18
19
20 if __name__ == '__main__':
21 move(x="1", y="0.2", z="0.3")
22 '''
23 运行结果
24 move 1 (0.20, 0.30)
25 [Finished in 0.2s]
26 '''
一个简单的例子，登录页面
1 # -*- coding: utf-8 -*-
2
3 #模拟网站登陆访问认证
4
5 name = 'abc'
6 password='123'
7
8 def certi(model):#装饰器
9 def outr(fun):#装饰器加参数需要多加一层嵌套
10 def login(*args,**kwargs):#为了兼容各类函数参数，添加 *args,**kwargs 不固定参数
11 if model=='password':
12 print('enter password')
13 user_name = raw_input('user_name ').strip()
14 paswd=raw_input('password ').strip()
15 if user_name==name and paswd==password:
16 print('pass')
17 return fun(*args,**kwargs)
18 else:
19 print('error ')
20 exit()
21 elif model=='lamp':
22 print('this is lamp')
23 return fun(*args,**kwargs)
24 else:
25 print('error')
26 return login
27 return outr
28
29
30 def indxe():
31 print('home page !!')
32
33 @certi(model='password')
34 def user():
35 print('user page !!')
36
37 @certi(model='lamp')
38 def bbs(name):
39 print('bbs %s!!'%name)
40
41
42
43 if __name__ == '__main__':
44 indxe()
45 user()
46 bbs(name='yjj')
47 '''
48 运行结果
49 home page !!
50 enter password
51 user_name abc
52 password 123
53 pass
54 user page !!
55 this is lamp
56 bbs yjj!!
57 '''
