面向对象-组合

组合为什么有什么

继承实现代码重用

class People:
    school="luffcity"
    def __init__(self, name, age, sex,):
        self.name = name
        self.age = age
        self.sex = sex

class Teacher(People):
    schoole='Luffycity'
    def __init__(self,name,age,sex,level,salary):
        super(Teacher,self).__init__(name,age,sex)
        self.level=level
        self.salary=salary
    def teach(self):
        print("%s is teaching" % self.name)
class Student(People):
    schoole = 'Luffycity'
    def __init__(self, name, age, sex, class_time):
        super(Student, self).__init__(name, age, sex)
        self.class_time=class_time
    def learn(self):
        print("%s is learning" % self.name)
t1=Teacher('alex',18,'male',10,3000)
s1=Student('zhangsan',28,'female','08:30:00')

 给老师添加其他属性，如课程信息，按如上方法，每次创建老师对象，都会传入相同参数，解决办法如下

class People:
    school="luffcity"
    def __init__(self, name, age, sex,):
        self.name = name
        self.age = age
        self.sex = sex

class Teacher(People):
    schoole='Luffycity'
    def __init__(self,name,age,sex,level,salary):
        super(Teacher,self).__init__(name,age,sex)
        self.level=level
        self.salary=salary
    def teach(self):
        print("%s is teaching" % self.name)

class Student(People):
    schoole = 'Luffycity'
    def __init__(self, name, age, sex, class_time):
        #super()关键字继承
        super(Student, self).__init__(name, age, sex)
        self.class_time=class_time
    def learn(self):
        print("%s is learning" % self.name)
#定义一个课程类
class Course:
    def __init__(self,course_name,course_price,course_period):
        self.course_name=course_name
        self.course_price=course_price
        self.course_period=course_period
#创建一个python课程对象
python=Course('python',3000,'3mons')
t1=Teacher('alex',18,'male',10,3000)
t2=Teacher('aglo',88,'male',90,1000)
#给t1添加课程对象
t1.course=python
#给t2添加课程对象
t2.course=python
#访问t1的课程对象
print(t1.course.course_name)
print(t1.course.course_price)
print(t1.course.course_period)
#访问t2的课程对象
print(t2.course.course_name)
print(t2.course.course_price)
print(t2.course.course_period)

在Course类中也可以添加其他方法，如添加一个查看课程信息的方法

class Course:
    def __init__(self,course_name,course_price,course_period):
        self.course_name=course_name
        self.course_price=course_price
        self.course_period=course_period
    def course_info(self):
        print("课程名<%s>课程价格<%s>课程周期<%s>" % (self.course_name,self.course_price,self.course_period))

访问course_info()方法

t1=Teacher('alex',18,'male',10,3000)
t1.course=python
t1.course.course_info()

即老师有课程

学生加一个日期属性

class Date:
    def __init__(self,year,mon,day):
        self.year=year
        self.mon=mon
        self.day=day
    def tell_info(self):
        print("%s-%s-%s" % (self.year,self.mon,self.day))
d=Date(2010,4,20)
student1=Student('张三',28,'female','08:30:00')
student1.birh=d
student1.birh.tell_info()