Python object oriented class inheritance and composite instance analysis
- 2020-10-07 18:45:42
- OfStack
This article provides an example of Python object-oriented class inheritance and composition. To share for your reference, the details are as follows:
In python3, all classes inherit from object by default, all classes that inherit from object are new classes, and subclasses of that subclass, Python3, are new classes, and subclasses that do not integrate with object are classic classes (classes that do not integrate with object and their subclasses are classic classes in Python2)
Inheritance is a way to create new classes with the benefit of less repetitive code
class People:
def __init__(self,name,age):
self.name=name
self.age=age
def walking(self):
print('%s is walking ' %self.name)
def talking(self):
print('%s is talking '%self.name)
class Teacher(People):
pass
class Student(People):
pass
t1=Teacher('egon',18)
print(t1.name,t1.age)
t1.walking()
t1.talking()
s1=Student('xiaobai',22)
print(s1.name,s1.age)
s1.talking()
s1.walking()
The execution result
[
egon 18
egon is walking
egon is talking
xiaobai 22
xiaobai is talking
xiaobai is walking
class People:
def __init__(self,name,age,sex):
self.name=name
self.age=age
self.sex=sex
def walking(self):
print('%s is walking ' %self.name)
def talking(self):
print('%s is talking '%self.name)
class Teacher(People):
def __init__(self,name,age,sex,level,salary):
People.__init__(name,age,sex)
self.level=level
self.salary=salary
def teaching(self):
People.talking(self)
print('%s is teaching'%self.name)
class Student(People):
def __init__(self,name,age,sex,group):
People.__init__(name,age,sex)
self.group=group
def studying(self):
People.talking(self)
print('%s is studying'%self.name)
combination
class Date:
def __init__(self,year,mon,day):
self.year=year
self.mon=mon
self.day=day
def tell_birth(self):
print(' Born in <%s> years <%s> month <%s> day '%(self.year,self.mon,self.day))
class Teacher:
def __init__(self,name,age,sex,year,month,day):
self.name=name
self.age=age
self.sex=sex
self.birth=Date(year,month,day)
def teaching(self):
print('%s is teaching'%self.name)
class Student:
def __init__(self,name,age,sex,year,mon,day):
self.name=name
self.age=age
self.sex=sex
self.birth=Date(year,mon,day)
def studying(self):
print('%s is studying'%self.name)
xiaobai=Student('xiaobai',22,'male','1995','3','16')
xiaobai.birth.tell_birth()
The execution result
[Born in < 1995 > years < 3 > month < 16 > day
]Inheritance and composition
class People:
def __init__(self,name,age,sex,year,mon,day):
self.name=name
self.age=age
self.sex=sex
self.birth=Date(year,mon,day)
def walking(self):
print('%s is walking ' %self.name)
def talking(self):
print('%s is talking '%self.name)
class Date:
def __init__(self,year,mon,day):
self.year=year
self.mon=mon
self.day=day
def tell_birth(self):
print(' Born in <%s> years <%s> month <%s> day '%(self.year,self.mon,self.day))
class Teacher(People):
def __init__(self,name,age,sex,level,salary,year,mon,day):
People.__init__(self,name,age,sex,year,mon,day)
self.level=level
self.salary=salary
def teaching(self):
People.talking(self)
print('%s is teaching'%self.name)
class Student(People):
def __init__(self,name,age,sex,year,mon,day,group):
People.__init__(self,name,age,sex,year,mon,day)
self.group=group
def studying(self):
People.talking(self)
print('%s is studying'%self.name)
The parent class is restricted
1. Subclasses must have superclass methods
2. A subclass must implement a method with the same name as the method of the parent class
import abc
class File(metaclass=abc.ABCMeta):
@abc.abstractclassmethod
def read(self):
pass
@abc.abstractclassmethod
def write(self):
pass
More about Python related content interested readers to view this site project: introduction to Python object-oriented programming and advanced tutorial ", "Python data structure and algorithm tutorial", "Python function using techniques", "Python string skills summary", "Python coding skills summary" and "introduction to Python and advanced tutorial"
I hope this article has been helpful in Python programming.