Python 面向對象

A simple sample with interface

import abc

country = 'China'


# Interface
class Humane(metaclass=abc.ABCMeta):
    def __init__(self):
        pass

    @abc.abstractmethod
    def conscience(self):
        pass

    @abc.abstractmethod
    def survival(self):
        pass


# Person
class Person(Humane):
    # Works, but not recommend
    job = "IT"

    # is the key to what will object own!
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def say(self):
        print(self.name)
        print(country)

    def conscience(self):
        print('conscience')

    def survival(self):
        print('survival')

    # This will treat a method as property way to use
    @property
    def eat(self):
        return 'eat'

    # Invoked by Class
    @classmethod
    def commonApprochInClass(cls):
        print(cls.job)

    # Static method
    @staticmethod
    def commonApproch(name, age):
        print(name + ' ' + age)


p1 = Person("John", 36)

# will print the memory path
print(p1)
# class dict, own both data properties and method properties
print(Person.__dict__)
# object dict, only has data properties
print(p1.__dict__)
print(p1.name)
print(p1.job)
p1.say()
Person.say(p1)
# @property
print(p1.eat)
# @classmethod
Person.commonApprochInClass()

Person.gender = "mail"
print(p1.gender)
print(p1.__dict__)

multiple extend

# In python, class support multiple extend
class God:
    def __init__(self):
        pass

    def eat(self):
        print('God eat')


class Animal(God):
    def __init__(self, gender, color):
        self.gender = gender
        self.color = color

    def eat(self):
        print('Animal eat')


class Canidae:
    def __init__(self):
        pass

    def eat(self):
        print('Canidae eat')


class Dog(Animal, Canidae):
    def __init__(self, gender, color, tail):
        # super(self).__init__(gender, color)
        Animal.__init__(self, gender, color)
        self.tail = tail

    def bark(self):
        print('Bark!!')


# When a class is going to use the method/property off its parents classes,
# it will apply depth-first in Python 2.7 and breadth-first in Python 3.x.

dog = Dog('male', 'Black', 'long')
dog.eat()
print(Dog.__mro__)

Reflection

class Vehicle:
    feature = 'Ugly'

    def __init__(self, name, type):
        self.name = name
        self.type = type

    def run(self):
        print('Vehicle run')

    def speak(self):
        print('Vehicle speak')


ve = Vehicle('Car', 'small')

# hasattr is checking if a obj can invoke a attr/method
print(hasattr(ve, 'name'))
print(hasattr(ve, 'feature'))
print(hasattr(ve, 'feature111'))

print(getattr(ve, 'name'))
print(getattr(ve, 'feature'))
print(getattr(ve, 'feature111', "None"))

setattr(ve, 'newFeature', 'Beautiful')
setattr(ve, 'jump', lambda x: x + 1)
print(getattr(ve, 'newFeature', "None"))

delattr(ve, 'newFeature')
print(getattr(ve, 'newFeature', "None"))