Inheritance (extending a class)

This lesson covers extending a class through inheritance in VB.NET, with the aim of reusing code across classes that share a nature.

Inherits creates a new class carrying the nature of an existing one. Inheritance lets you gather the shared work into a parent class and write only the differences in each child.

The sample code makes Dog inherit the parent Animal with Inherits Animal. A parent function marked Overridable is replaced in the child with Overrides, changing only the sound message.

A common early stumble is that overriding needs the Overridable and Overrides pair. Forget Overridable on the parent and the child cannot override it, which is a compile error.

In professional work, inheritance is used wherever several classes share a nature — kinds of animal, kinds of shape. Gathering the common part into a parent reduces duplication.

📖 Reference code

Class Animal
    Public Name As String
    Public Sub New(name As String)
        Me.Name = name
    End Sub
    Public Overridable Function Speak() As String
        Return Name & " makes a sound"
    End Function
End Class

Class Dog
    Inherits Animal
    Public Sub New(name As String)
        MyBase.New(name)
    End Sub
    Public Overrides Function Speak() As String
        Return Name & " says ""Woof"""
    End Function
End Class

Dim dog As New Dog("Rex")
Console.WriteLine(dog.Speak())

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run VB.NET directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).