Python裝飾器用法實例分析
本文實例講述了Python裝飾器用法。分享給大家供大家參考,具體如下:
無參數的裝飾器
#coding=utf-8
def log(func):
def wrapper():
print 'before calling ',func.__name__
func()
print 'end calling ',func.__name__
return wrapper
@log
def hello():
print 'hello'
@log
def hello2(name):
print 'hello',name
if __name__=='__main__':
hello()
運行結果:
before calling hello
hello
end calling hello
帶參數的裝飾器:
#coding=utf-8
def log(func):
def wrapper(name):
print 'before calling ',func.__name__
func(name)
print 'end calling ',func.__name__
return wrapper
@log
def hello(name):
print 'hello',name
@log
def hello2(name):
print 'hello',name
if __name__=='__main__':
hello('haha')
運行結果:
before calling hello
hello haha
end calling hello
多個參數的時候:
#coding=utf-8
def log(func):
'''
*無名字的參數
**有名字的參數
:param func:
:return:
'''
def wrapper(*args,**kvargs):
print 'before calling ',func.__name__
print 'args',args,'kvargs',kvargs
func(*args,**kvargs)
print 'end calling ',func.__name__
return wrapper
@log
def hello(name,age):
print 'hello',name,age
@log
def hello2(name):
print 'hello',name
if __name__=='__main__':
hello('haha',2)
hello(name='hehe',age=3)
輸出:
end calling hello
before calling hello
args () kvargs {'age': 3, 'name': 'hehe'}
hello hehe 3
end calling hello
裝飾器里帶參數的情況
本質就是嵌套函數
#coding=utf-8
def log(level,*args,**kvargs):
def inner(func):
def wrapper(*args,**kvargs):
print level,'before calling ',func.__name__
print level,'args',args,'kvargs',kvargs
func(*args,**kvargs)
print level,'end calling ',func.__name__
return wrapper
return inner
@log(level='INFO')
def hello(name,age):
print 'hello',name,age
@log
def hello2(name):
print 'hello',name
if __name__=='__main__':
hello('haha',2)
運行輸出:
INFO before calling hello
INFO args ('haha', 2) kvargs {}
hello haha 2
INFO end calling hello
更多關于Python相關內容可查看本站專題:《Python數據結構與算法教程》、《Python Socket編程技巧總結》、《Python函數使用技巧總結》、《Python字符串操作技巧匯總》及《Python入門與進階經典教程》
希望本文所述對大家Python程序設計有所幫助。

