Python学习之路：staticmethod classmethod property方法

参考链接：http://www.cnblogs.com/alex3714/articles/5213184.html

静态方法

　　只是名义上归类管理，实际上在静态方法里访问不了类或实例中的任何属性

class Dog(object):
    def __init__(self,name):
        self.name = name

    @staticmethod #实际上跟类没什么关系了
    def eat(self):
        print("%s is eating %s"%(self.name,'dd'))

    def talk(self):
        print("%s is talking"%self.name)


d = Dog("ChenRH")
d.eat(d)
d.talk()

 类方法：

　　只能访问类变量，不能访问实例变量

class Dog(object):
    #n = 3333
    name = "Huazai"
    def __init__(self,name):
        self.name = name

    #@staticmethod #实际上跟类没什么关系了
    @classmethod
    def eat(self):
        print("%s is eating %s"%(self.name,'dd'))

    def talk(self):
        print("%s is talking"%self.name)


d = Dog("ChenRH")
d.eat()
d.talk()

 属性方法：

　　把一个方法变成一个静态属性

class Dog(object):
    #n = 3333
    name = "Huazai"
    def __init__(self,name):
        self.name = name

    #@staticmethod #实际上跟类没什么关系了
    #@classmethod
    @property #attribute
    def eat(self):
        print("%s is eating %s"%(self.name,'dd'))

    # def talk(self):
    #     print("%s is talking"%self.name)


d = Dog("ChenRH")
d.eat

class Dog(object):
    #n = 3333
    name = "Huazai"
    def __init__(self,name):
        self.name = name
        self.__food =None

    #@staticmethod #实际上跟类没什么关系了
    #@classmethod
    @property #attribute，把一个方法变成属性
    def eat(self):
        print("%s is eating %s"%(self.name,self.__food))


    @eat.setter#修改属性
    def eat(self,food):
        print("set to food:",food)
        self.__food = food

    @eat.deleter#删除私有属性
    def eat(self):
        del self.__food
        print("删完了")

    # def talk(self):
    #     print("%s is talking"%self.name)


d = Dog("ChenRH")
d.eat
d.eat = "baozi"

del d.eat

 静态属性方法适用场景举例：

你想知道一个航班当前的状态，是到达了、延迟了、取消了、还是已经飞走了， 想知道这种状态你必须经历以下几步:

1. 连接航空公司API查询

2. 对查询结果进行解析 

3. 返回结果给你的用户

因此这个status属性的值是一系列动作后才得到的结果，所以你每次调用时，其实它都要经过一系列的动作才返回你结果，但这些动作过程不需要用户关心， 用户只需要调用这个属性就可以，明白 了么？

class Flight(object):
    def __init__(self,name):
        self.flight_name = name


    def checking_status(self):
        print("checking flight %s status " % self.flight_name)
        return  1


    @property
    def flight_status(self):
        status = self.checking_status()
        if status == 0 :
            print("flight got canceled...")
        elif status == 1 :
            print("flight is arrived...")
        elif status == 2:
            print("flight has departured already...")
        else:
            print("cannot confirm the flight status...,please check later")

    @flight_status.setter #修改
    def flight_status(self,status):
        status_dic = {
            0 : "canceled",
            1 :"arrived",
            2 : "departured"
        }
        print("33[31;1mHas changed the flight status to 33[0m",status_dic.get(status) )

    @flight_status.deleter  #删除
    def flight_status(self):
        print("status got removed...")

f = Flight("CA980")
f.flight_status
f.flight_status =  2 #触发@flight_status.setter
del f.flight_status #触发@flight_status.deleter