python 的一些特性
class Student(object):
say="this is a student class"
def __init__(self,name,age):#构造器
self.name = name
self.age = age
@classmethod#类方法
def showClassMethod(cls):
print "call classmethod"
print cls.say
@staticmethod#静态方法，属于类
def showStaticMethod():
print "call static method"
print Student.say
@property#包装器定义属性
def sex(self):
print "call property"
return self._sex
@sex.setter#包装器设置sex
def sex(self,value):
print "call setter"
self._sex = value
def getSex(self):#外部获取sex属性
return self._sex
def showAll(self):#类对象调用
print "call instance method"
print self.age,self.name,self.sex,self.getSex()
def __del__(self):#析构函数
print "call destructor"
def __str__(self):#获取类对象的字符串描述
return "student object:(name:%s)(age:%d)" % (self.name,self.age)
def __repr__(self):#调试用 例如在控制台调用：s
return self.__str__()
def __getattr__(self, item):#获取非定义的属性
if item == "score":
return lambda :99
elif item == "dog":
return "xiaohuang"
else:
raise "attr error"
def __call__(self, *args, **kwargs): #调用自己
print "__call__ self:"
for i in range(len(args)):#打印元组
print args[i]
for i in kwargs:#打印键值对
print i,kwargs[i]
print "call:my name is zhengjinwei"
Student.showClassMethod() #调用类方法
s = Student("zhengjinwei",24)
s.sex = "male" #调用sex的包装器，此处要注意的是Student类必须继承自object才能使用包装器
s.grade = "1" #动态创建属性
print s.grade
print s #调用 __str__
print s.score() #调用__getattr__
print s.dog #调用__getattr__
if callable(s):
s(1,2,3,name="zjw",age=24) #调用 __call__
s.showClassMethod()
s.showStaticMethod()
s.showAll()
结果：
<span style="font-size:18px;">call classmethod this is a student class call setter 1 student object:(name:zhengjinwei)(age:24) 99 xiaohuang __call__ self: 1 2 3 age 24 name zjw call:my name is zhengjinwei call classmethod this is a student class call static method this is a student class call instance method 24 zhengjinwei call property male male call destructor </span>