NEW INHERITANCE IN VB.NET

1. Example Of Inheritance
(Console Apps)(modified)
• Simple Inheritance
• Hierarchical Inheritance
• Multi-level Inheritance
• Hybrid Inheritance
• Multiple Inheritance
Surojit
Paul

2. page2
Simple Inheritance
'Example of Simple Inheritance
'create a phone class
Class Phone
'all phones can make a call
Public Sub CanCall()
Console.WriteLine("Yes, you can call")
End Sub
End Class
'smartphone is a phone but you can do much more
Class SmartPhone : Inherits Phone
'only smart phones are capable of gaming and chating
Public Sub canPlayPUBG()
Console.WriteLine("Yes, you can play PUBG")
End Sub
Public Sub canChat()
Console.WriteLine("Yes, you can chat")
End Sub
End Class
Module Module1
Sub Main()
'create a Phone name 'nokia'
Dim nokia As New Phone
Console.WriteLine("nokia")
nokia.CanCall() 'can only make calls
Console.WriteLine()
'create a SmartPhone name 'OnePlus7'
Dim OnePlus7 As New SmartPhone
Console.WriteLine("OnePlus7")
OnePlus7.CanCall() 'make calls
OnePlus7.canPlayPUBG() 'can play game
OnePlus7.canChat() 'and chat
Console.ReadKey()
End Sub
End Module

3. page3
Hierarchical Inheritance
'Example Of Hierarchical inheritance
'Create a Tiger class
Class Tiger
Public Sub HowmanyLegs()
'a tiger always has 4 legs no matter what kind of it is.
Console.WriteLine("Legs: 4 Lengs")
End Sub
Public Sub location()
'a tiger need some place to live
'but differ with the kind of tiger
Console.WriteLine("Location Unknown")
End Sub
End Class
Class RoyalBengalTiger : Inherits Tiger
'only royal bengal tiger have visible dark strips
Public Sub hasStripe()
Console.WriteLine("Strip Present")
End Sub
'overloads the location from 'Tiger' Class
Public Overloads Sub location()
Console.WriteLine("Location: Sundarban- West Bengal and Bangla-
desh")
End Sub
End Class
Class SnowLepard : Inherits Tiger
'only snowlepard are white
Public Sub Color()
Console.WriteLine("Almost White")
End Sub
'overloads the location from 'Tiger' Class
Public Overloads Sub location()
Console.WriteLine("location: Tundra, in parts of alaska and Russia")
End Sub
End Class

4. page4
Module Module1
Sub Main()
'all tigers have two things in common
'1. location
'2. Number of Legs
'create a Tiger name 'LostLeg'
'in this case type of tiger is not specified
Dim LostLeg As New Tiger
LostLeg.HowmanyLegs()
LostLeg.location()
Console.WriteLine()
'create a RoyalBengalTiger name 'gavin'
Dim gavin As New RoyalBengalTiger
gavin.HowmanyLegs()
gavin.location()
gavin.hasStripe() 'only a Royal Bengal Tiger
'has hasStripe() method
Console.WriteLine()
'create a SnowLepard name 'swift'
Dim swift As New SnowLepard
swift.HowmanyLegs()
swift.location()
swift.Color() ' only a snow lepard has Color() method
Console.ReadKey()
End Sub
End Module

5. page5
Multi-Level Inheritance
'base Class
Class Drinks
Public Sub isLiqud()
Console.WriteLine("Drink is Liquid")
End Sub
Public Sub isDrinkableByChild()
Console.WriteLine("Unknown")
End Sub
End Class
'inherits Drinks
Class SoftDrink : Inherits Drinks
Public Overloads Sub isDrinkableByChild()
Console.WriteLine("Yes, a child can Consume")
End Sub
Public Sub needSugar()
Console.WriteLine("Sugar ?: Yes, need Sugar")
End Sub
End Class
'inherits SoftDrinks
Class Cola : Inherits SoftDrink
Public Sub isHaveSoda()
Console.WriteLine("Soda ? : yes , have soda")
End Sub
End Class
Module Module1
Sub Main()
Dim LemonJuice As New Drinks
Console.WriteLine("LemonJuice")
LemonJuice.isLiqud()
LemonJuice.isDrinkableByChild()
Console.WriteLine()
Dim AppleJuice As New SoftDrink
Console.WriteLine("AppleJuice")
AppleJuice.isLiqud()
AppleJuice.isDrinkableByChild()
AppleJuice.needSugar()
Console.WriteLine()
Dim Pepsi As New Cola
Console.WriteLine("Pepsi")
Pepsi.isLiqud()
Pepsi.isDrinkableByChild()
Pepsi.needSugar()
Pepsi.isHaveSoda()

6. page6
Console.ReadKey()
End Sub
End Module

7. page7
Hybrid Inheritance
'base Class
Class Drinks
Public Sub isLiqud()
Console.WriteLine("Drink is Liquid")
End Sub
Public Sub isDrinkableByChild()
Console.WriteLine("Unknown")
End Sub
End Class
'inherits Drinks
Class SoftDrink : Inherits Drinks
Public Overloads Sub isDrinkableByChild()
Console.WriteLine("Yes, a child can Consume")
End Sub
Public Sub needSugar()
Console.WriteLine("Sugar ?: Yes, need Sugar")
End Sub
End Class
'inherits Drinks
Class HardDrinks : Inherits Drinks
Public Overloads Sub isDrinkableByChild()
Console.WriteLine("No, illegal to Cosume by a child")
End Sub
Public Sub haveAlcohol()
Console.WriteLine("Alcohol ?: Yes, have alcohol")
End Sub
End Class
'inherits SoftDrinks
Class Cola : Inherits SoftDrink
Public Sub isHaveSoda()
Console.WriteLine("Soda ? : yes , have soda")
End Sub
End Class
'inherits HardDrinks
Class Beer : Inherits HardDrinks
Public Sub isBadForHealth()
Console.WriteLine("Bad ?: Yes!, very much.")
End Sub
End Class

8. page8
Module Module1
Sub Main()
Dim LemonJuice As New Drinks
Console.WriteLine("LemonJuice")
LemonJuice.isLiqud()
LemonJuice.isDrinkableByChild()
Console.WriteLine()
Dim AppleJuice As New SoftDrink
Console.WriteLine("AppleJuice")
AppleJuice.isLiqud()
AppleJuice.isDrinkableByChild()
AppleJuice.needSugar()
Console.WriteLine()
Dim Pepsi As New Cola
Console.WriteLine("Pepsi")
Pepsi.isLiqud()
Pepsi.isDrinkableByChild()
Pepsi.needSugar()
Pepsi.isHaveSoda()
Console.WriteLine()
Dim AlcoholicDrink As New HardDrinks
Console.WriteLine("AlcoholicDrink")
AlcoholicDrink.isLiqud()
AlcoholicDrink.isDrinkableByChild()
AlcoholicDrink.haveAlcohol()
Console.WriteLine()
Dim BeerCocktail As New Beer
Console.WriteLine("BeerCocktail")
BeerCocktail.isLiqud()
BeerCocktail.isDrinkableByChild()
BeerCocktail.haveAlcohol()
BeerCocktail.isBadForHealth()
Console.ReadKey()
End Sub
End Module

9. page9
Multiple-Inheritance 1 (Interface)
Interface AnimalCharacter
Sub howmanyLegs()
Sub talk()
End Interface
Class Animal
Public Sub canWalk()
Console.WriteLine("Yes, This animal Can Walk")
End Sub
End Class
Class dog : Inherits Animal : Implements AnimalCharacter
Public Sub howmanyLegs() Implements AnimalCharacter.howmanyLegs
Console.WriteLine("Dogs have 4 legs")
End Sub
Public Sub talk() Implements AnimalCharacter.talk
Console.WriteLine("Make Sound:- bow bow")
End Sub
End Class
Class human : Inherits Animal : Implements AnimalCharacter
Public Sub howmanyLegs() Implements AnimalCharacter.howmanyLegs
Console.WriteLine("Human have 2 legs")
End Sub
Public Sub talk() Implements AnimalCharacter.talk
Console.WriteLine("Make Sound:- Hello, i am a human")
End Sub
End Class
Module Module1
Sub Main()
Dim barky As New dog
Console.WriteLine("Barky")
barky.howmanyLegs() 'from interface so value can differ (4 legs)
barky.talk() 'from interface so value can differ
barky.canWalk() ' from base class so value will be same
Console.WriteLine()
Dim jack As New human
Console.WriteLine("Jack")
jack.howmanyLegs() 'from interface so value can differ (2 legs)
jack.talk() 'from interface so value can differ

10. page10
jack.canWalk() ' from base class so value will be same
Console.ReadKey()
End Sub
End Module

11. page11
Interface interface1
Sub add() 'to add two number
End Interface
Interface interface2
Sub multiply() 'to multiply two number
End Interface
'this class will share methods of both interfaces
Public Class MathClass : Implements interface1, interface2
Private number1, number2 As Integer
Public Sub New(ByVal n1 As Integer, ByVal n2 As Integer) 'this called a Constructer
number1 = n1
number2 = n2
End Sub
Public Sub add() Implements interface1.add 'from interface1
Console.WriteLine("Add: " & number1 & "+" & number2 & " = " & number2 + number1)
End Sub
Public Sub multiply() Implements interface2.multiply 'from interface2
Console.WriteLine("Multiply: " & number1 & "*" & number2 & " = " & number2 * number1)
End Sub
End Class
Module Module1
Sub Main()
' change this two number to chnage the output
Dim equ1 As New MathClass(12, 2)
equ1.add() 'from interface1
equ1.multiply() 'from interface2
Console.ReadKey()
End Sub
End Module
Multiple-Inheritance 2 (2 Interface)