Overriding

Python Overriding

• It is nothing but rewriting super class method in sub class.

• Rules to override
• Class must be inherited

• Method name must be same

• Same no. of parameters should be there.

• Python provides 

• Constructor Overriding

                        Rewriting the constructor in  child class.

 #program for constructor overriding

 class A :
     def __init__(self):
         print("This is class A constructor")

 class B(A) :
     def __init__(self):
         print("This is class B constructor")

 a = A()
 b = B()

 #output

 This is class A constructor
 This is class B constructor

                        How to call Super Class constructor in sub Class ?

 #program for calling super class constructor in sub class

 class A :
     def __init__(self):
         print("This is class A constructor")

 class B(A) :
     def __init__(self):
         super().__init__()
         print("This is class B constructor")

 b = B()            # creating object to class b

 #output

 This is class A constructor
 This is class B constructor

• Method Overriding

 #program for Method Overriding

 class A :
     def __init__(self):
         print("This is class A constructor")
 
     def add(self, a, b):
         print("add function of class A")
         return a+b;

 class B(A) :
     def add(self, a, b):
         print("add function of class B")
         return a-b;


 b = B()
 c = b.add(10, 5)
 print("c :", c)

 #output

 This is class A constructor
 add function of class B
 c : 5