python面向对象编程

Posted 2021-01-14 zhujunjie

       继承介绍：

 

 

class Parent1(object):
    pass

class Parent2:
    pass

class Sub1(Parent1):
    pass

class Sub2(Parent1,Parent2):
    pass

print(Sub1.__bases__)
print(Sub2.__bases__)

print(Parent1.__bases__)
print(Parent2.__bases__)





class Foo:
    x=1
    pass
obj=Foo()
obj.x=3
print(obj.x)



继承解决类与类代码冗余的问题：

class OldboyPeople:
    school = ‘Oldboy‘
    def __init__(self, name, age, gender):
        self.name = name
        self.age = age
        self.gender = gender


print(OldboyPeople.__init__)


class OldboyStudent(OldboyPeople):
    def __init__(self,name,age,gender):
        self.name = name
        self.age = age
        self.gender = gender


    def choose_course(self):
        print(‘%s is choosing course‘ %self.name)


class OldboyTeacher(OldboyPeople):
    def __init__(self,name,age,gender,level,salary):
        self.name = name
        self.age = age
        self.gender = gender
        OldboyPeople.__init__(self,name,age,gender)

        self.level=level
        self.salary=salary

    def score(self,stu,num):
        stu.num=num
        print(‘老师%s给学生%s打分%s‘ %(self.name,stu.name,num))

stu=OldboyStudent(‘kevin‘,38,‘male‘) #__init___(stu1,‘kevin‘,38,‘male‘)
print(stu.__dict__)
tea=OldboyTeacher(‘egon‘,18,‘male‘,10,3000) #__init___(tea,‘egon‘,18,‘male‘,10,3000)
print(tea.__dict__)
print(stu.school)
print(tea.school)

单继承背景下属性的查找顺序：

class Foo:
    def f1(self):
        print(‘Foo.f1‘)

    def f2(self):
        print(‘Foo.f2‘)
        self.f1() #obj.f1()

class Bar(Foo):
    def f1(self):
        print(‘Bar.f1‘)

obj=Bar()
obj.f2()


class E:
    xxx=‘E‘
    pass

class F:
    xxx=‘F‘
    pass

class B(E):
    xxx=‘B‘
    pass

class C(F):
    xxx=‘C‘
    pass

class D:
    xxx=‘D‘
    pass

class A(B,C,D):
    xxx=‘A‘
    pass

# obj=A()
# obj.xxx=111
# print(obj.xxx)

print(A.mro())


class G:
    xxx=‘G‘

class E(G):
    xxx=‘E‘
    pass

class F(G):
    xxx=‘F‘
    pass

class B(E):
    xxx=‘B‘
    pass

class C(F):
    xxx=‘C‘
    pass

class D(G):
    xxx=‘D‘
    pass

class A(B,C,D):
    xxx=‘A‘
    pass


print(A.mro())