python学习之面向对象property、继承与菱形问题作业

作业一：自己试验一下菱形问题下的属性查找顺序

#    经典类：深度优先，会在检索第一条分支的时候就直接一条道走到黑，即会检索大脑袋（共同的父类）

#    新式类：广度优先，会在检索最后一条分支的时候检索大脑袋

#在python3中所有类都是新式类，无经典类、新式类之分；
#在python2中类分为经典类和新式类
#以下代码是在python2中运行的代码
class G: # 在python2中，未继承object的类及其子类，都是经典类
    def test(self):
        print('from G')
    pass

class E(G):
    def test(self):
        print('from E')
    pass

class F(G):
    def test(self):
        print('from F')

class B(E):
    def test(self):
        print('from B')
    pass

class C(F):
    def test(self):
        print('from C')

class D(G):
    def test(self):
        print('from D')

class A(B,C,D):
    def test(self):
        print('from A')
    pass

# 新式类

# print(A.mro()) # A->B->E->C->F->D->G->object

# 经典类：在python2中没有继承object类及其子子孙孙类都是经典类

# print(A.mro()) # A->B->E->G->C->F->D

obj = A()
obj.test()

# 总结：类相关的属性查找（类名.属性，该类的对象.属性），都是参照该类的mro

作业二：在昨天作业的基础之上

1、引入属性访问控制+property

2、引入继承与派生的概念来减少代码冗余

注意：要满足什么"是"什么的关系，不满足"是"的关系不要去继承

class School():

​    school_name = 'Oldboy'
​    def __init__(self,nick_name,address):
​        self.nick_name = nick_name
​        self.address = address
​        self.classes = []

​    def related_class(self,class_obj):
​        self.classes.append(class_obj)

​    def tell_info(self):
​        print('='*22+' %s '%self.nick_name+'='*22)
​        for class_obj in self.classes:
​            class_obj.tell_info()

class Class():

​    def __init__(self,name):
​        self.name = name
​        self.course = None

​    def related_course(self,course_obj):
​        self.course = course_obj

​    def tell_info(self):
​        print('%s     '%self.name,end='')
​        self.course.tell_info()

class Course():

​    def __init__(self,name,period,price):
​        self.name = name
​        self.period = period
​        self.price = price

​    def tell_info(self):
​        print('<课程名:%s 周期:%s 价格:%s>'%(self.name,self.period,self.price))



class Student():

​    def __init__(self,name,age,sex):
​        self.name = name
​        self.age = age
​        self.sex = sex
​        self.course = []
​        self.class_name = None

​    def related_course(self,course_name):
​        self.course.append(course_name)
​    def related_class(self,class_name):
​        self.class_name = class_name

​    def tell_info(self):
​        print('='*20+' 学生信息 '+'='*20)
​        print('姓名:%s 年龄:%s 性别:%s 班级:%s'%(
​            self.name,self.age,self.sex,self.class_name
​        ))
​        print('课程信息:')
​        for course in self.course:
​            course.tell_info()

cour1 = Course('python开发','6 months','20000')
cour2 = Course('linux运维','6 months','18000')

class1 = Class('python14期')
class1.related_course(cour1)
class2 = Class('python 9期')
class2.related_course(cour1)
class3 = Class('linux 25期')
class3.related_course(cour2)

sch1 = School('老男孩魔都校区','上海')
sch1.related_class(class1)
sch1.related_class(class3)
sch2 = School('老男孩帝都校区','北京')
sch2.related_class(class2)

stu1 = Student('vincent','18','male')
stu1.related_class(class1.name)
stu1.related_course(cour1)
stu1.related_course(cour2)
stu1.tell_info()