## ----- inheritance polymorphism
Inheritance: subclasses fully owns the data parent class
polymorphism: Each subclass has its own method of diversification data can be completely independent of the parent class, you can inherit the parent class on the basis of the increase
Inherited shortcut Ctrl + o
1. Data Inheritance
No instances of subclasses init function completely automatically inherit the parent class data
class A:
def __init__(self, name, age):
self.name = name
self.age = age
def sya(self):
print('say...')
B class (A):
Pass
B = B ( 'LILI', 25) to be filled # parameters, or error
Subclass has its own instance of init function
either fully inherit the parent class attributes, increase their attributes on the basis of
class A:
DEF the __init __ (Self, name = None, Age = None):
the self.name name =
self.age = Age
class B(A):
def __init__(self, name, age, sex):
super().__init__(name, age)
self.sex = sex
b = B('LI',25, 'm')
print(b.__dict__)
/ Or completely rewritten to use their own property
class A:
def __init__(self, name=None, age=None):
self.name = name
self.age = age
class B(A):
def __init__(self, name, sex):
self.name = name
self.sex = sex
b = B('LI', 'm')
print(b.__dict__)
Inherited methods: the subclass automatically inherits the parent class method, you do not need to rewrite the code
May be added to the method of the parent class
class A:
DEF the __init __ (Self, name, Age):
the self.name name =
self.age = Age
def sya(self):
print('say...')
class B(A):
def him (self):
super (). He ()
Completely rewritten
class A:
DEF the __init __ (Self, name, Age):
the self.name name =
self.age = Age
def sya(self):
print('say...')
class B(A):
def him (self):
print ( 'hello')
Built-in functions
isinstance (object type)
Returns whether the specified object is an object of some class.
issubclass (type, type)
Returns the specified type is part of a type.