Python进阶三：面向对象基础

初始化实例属性：输入关键字信息attr=‘attr1’可以用kw.iteritems()

class Person(object):
    def __init__(self,name,gender,birth,**kw):
        self.name=name
        self.gender=gender
        self.birth=birth
        for k,v in kw.iteritems():
            setattr(self,k,v)

xiaoming = Person('Xiao Ming', 'Male', '1990-1-1', job='Student')

print xiaoming.name
print xiaoming.job

class Person(object):
    def __init__(self, name, score):
        self.name=name
        self.__score=score

p = Person('Bob', 59)

print p.name
print p.__score

定义类属性：直接绑定在类上的属性不需要创建实例，可以直接用类名访问(类属性和实例属性冲突：先寻找实例属性赋值或者引用然后再找类属性)

class Person(object):
    count = 0
    def __init__(self,name):
        self.name=name
        Person.count=Person.count+1
p1 = Person('Bob')
print Person.count

p2 = Person('Alice')
print Person.count

p3 = Person('Tim')
print Person.count

class Person(object):

    def __init__(self, name, score):
        self.name=name
        self.__score=score

    def get_grade(self):
        return self.__score

p1 = Person('Bob', 90)
p2 = Person('Alice', 65)
p3 = Person('Tim', 48)

print p1.get_grade()
print p2.get_grade()
print p3.get_grade()

import types
def fn_get_grade(self):
    if self.score >= 80:
        return 'A'
    if self.score >= 60:
        return 'B'
    return 'C'

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

p1 = Person('Bob', 90)
p1.get_grade = types.MethodType(fn_get_grade, p1, Person)  #将fn_get_grade绑定到P1实例
print p1.get_grade()
# => A
p2 = Person('Alice', 65)
print p2.get_grade()
# ERROR: AttributeError: 'Person' object has no attribute 'get_grade'
# 因为p2实例并没有绑定get_grade

class Person(object):

    __count = 0
    @classmethod
    def how_many(ck):
        return ck.__count
    def __init__(self,name):
        self.name=name
        Person.__count=Person.__count+1
print Person.how_many()

p1 = Person('Bob')

print Person.how_many()

Python进阶三：面向对象基础

原文：http://blog.csdn.net/a353833082/article/details/46893809