标签：tar imm name show UNC ide 目的 class cli
对扩展开放，对修改是封闭
装饰它人的，器指的是任意可调用对象，现在的场景装饰器-》函数，被装饰的对象也是-》函数
1、不修改被装饰对象的源代码
2、不修改被装饰对象的调用方式
在遵循1,2的前提下为被装饰对象添加上新功能
错误的示范
import time
def index():
time.sleep(3)
print(‘welecome to index‘)
def timmer(func):
start=time.time()
func()
stop=time.time()
print(‘run time is %s‘ %(stop-start))
timmer(index)
import time
def index():
time.sleep(3)
print(‘welecome to index‘)
def timmer(func):
# func=index #最原始的index
def inner():
start=time.time()
func() #最原始的index
stop=time.time()
print(‘run time is %s‘ %(stop-start))
return inner
index=timmer(index) #index=inner
# print(f)
index() #inner()
在被装饰对象正上方单独一行写上，@装饰器名
@deco1
@deco2
@deco3
def foo():
pass
foo=deco1(deco2(deco3(foo)))
import time
def timmer(func):
def inner():
start=time.time()
res=func()
stop=time.time()
print(‘run time is %s‘ %(stop-start))
return res
return inner
@timmer #index=timmer(index)
def index():
time.sleep(1)
print(‘welecome to index‘)
return 1111
res=index() #res=inner()
print(res)
import time
def timmer(func):
def inner(*args,**kwargs):
start=time.time()
res=func(*args,**kwargs)
stop=time.time()
print(‘run time is %s‘ %(stop-start))
return res
return inner
@timmer #index=timmer(index)
def index(name):
time.sleep(1)
print(‘welecome %s to index‘ %name)
return 1111
res=index(‘egon‘) #res=inner(‘egon‘)
print(res)
@timmer #home=timmer(home)
def home(name):
print(‘welcome %s to home page‘ %name)
home(‘egon‘) #inner(‘egon‘)
import time def auth(func): # func=index def inner(*args,**kwargs): name=input(‘name>>: ‘).strip() password=input(‘password>>: ‘).strip() if name == ‘egon‘ and password == ‘123‘: print(‘login successful‘) return func(*args,**kwargs) else: print(‘login err‘) return inner @auth def index(name): time.sleep(1) print(‘welecome %s to index‘ %name) return 1111 res=index(‘egon‘) print(res)
#有参装饰器
import time def auth2(engine=‘file‘): def auth(func): # func=index def inner(*args,**kwargs): if engine == ‘file‘: name=input(‘name>>: ‘).strip() password=input(‘password>>: ‘).strip() if name == ‘egon‘ and password == ‘123‘: print(‘login successful‘) return func(*args,**kwargs) else: print(‘login err‘) elif engine == ‘mysql‘: print(‘mysql auth‘) elif engine == ‘ldap‘: print(‘ldap auth‘) else: print(‘engin not exists‘) return inner return auth @auth2(engine=‘mysql‘) #@auth #index=auth(index) #index=inner def index(name): time.sleep(1) print(‘welecome %s to index‘ %name) return 1111 res=index(‘egon‘) #res=inner(‘egon‘) print(res)
import time def timmer(func): def inner(*args,**kwargs): start=time.time() res=func(*args,**kwargs) stop=time.time() print(‘run time is %s‘ %(stop-start)) return res return inner def auth2(engine=‘file‘): def auth(func): # func=index def inner(*args,**kwargs): if engine == ‘file‘: name=input(‘name>>: ‘).strip() password=input(‘password>>: ‘).strip() if name == ‘egon‘ and password == ‘123‘: print(‘login successful‘) return func(*args,**kwargs) else: print(‘login err‘) elif engine == ‘mysql‘: print(‘mysql auth‘) elif engine == ‘ldap‘: print(‘ldap auth‘) else: print(‘engin not exists‘) return inner return auth @auth2(engine=‘file‘) @timmer def index(name): time.sleep(1) print(‘welecome %s to index‘ %name) return 1111 res=index(‘egon‘) print(res)
from functools import wraps import time def timmer(func): @wraps(func) def inner(*args,**kwargs): start=time.time() res=func(*args,**kwargs) stop=time.time() print(‘run time is %s‘ %(stop-start)) return res # inner.__doc__=func.__doc__ # inner.__name__=func.__name__ return inner @timmer def index(name): #index=inner ‘‘‘index 函数。。。。。‘‘‘ time.sleep(1) print(‘welecome %s to index‘ %name) return 1111 # res=index(‘egon‘) # print(res) print(help(index))
标签：tar imm name show UNC ide 目的 class cli
原文地址：https://www.cnblogs.com/linxidong/p/11190972.html
