Python面向对象编程基础

来源：互联网发布：linux命令行怎么打开编辑：程序博客网时间：2024/04/30 03:16

面向对象编程基础

定义类并创建实例

class Person(object):    passxiaoming = Person()xiaohong = Person()print xiaomingprint xiaohongprint xiaoming == xiaohong

创建实例属性

class Person(object):    passp1 = Person()p1.name = 'Bart'p2 = Person()p2.name = 'Adam'p3 = Person()p3.name = 'Lisa'L1 = [p1, p2, p3]L2 = sorted(L1,lambda x,y:cmp(x.name,y.name))print L2[0].nameprint L2[1].nameprint L2[2].name

初始化实例属性

class Person(object):    def __init__(self,name,gender,birth,job):        self.name = name        self.gender = gender        self.birth = birth        self.job = jobxiaoming = Person('Xiao Ming', 'Male', '1990-1-1', job='Student')print xiaoming.nameprint xiaoming.job

访问限制

class Person(object):    def __init__(self, name, score):        self.name =  name        self.__score = scorep = Person('Bob', 59)print p.nameprint p.__score

创建类属性

class Person(object):    count = 0    def __init__(self,name):        Person.count = Person.count + 1        self.name = name        p1 = Person('Bob')print Person.countp2 = Person('Alice')print Person.countp3 = Person('Tim')print Person.count

定义实例方法

class Person(object):    def __init__(self, name, score):        self.name = name        self.__score = score    def get_grade(self):        if(self.__score < 60):            return "C"        elif(self.__score >= 90):            return "A"        else:            return "B"        p1 = Person('Bob', 90)p2 = Person('Alice', 65)p3 = Person('Tim', 48)print p1.get_grade()print p2.get_grade()print p3.get_grade()

定义类方法

class Person(object):    __count = 0    @classmethod    def how_many(cls):        return cls.__count    def __init__(self,name):        self.name = name        Person.__count = Person.__count + 1print Person.how_many()p1 = Person('Bob')print Person.how_many()

0 0