In visual basic, Method Overriding means override a base class method in the derived class by creating a method with the same name and signatures to perform a different task. The Method Overriding in visual basic can be achieved by using Overridable & Overrides keywords along with the inheritance principle.
Suppose, if we want to change the behavior of the base class method in a derived class, we need to use method overriding. The base class method which we want to override in the derived class that needs to be defined with an Overridable keyword and we need to use Overrides keyword in derived class while defining the method with the same name and parameters then only we can override the base class method in the derived class.
In visual basic, the Method Overriding is also called as run time polymorphism or late binding. Following is the code snippet of implementing a method overriding in a visual basic programming language.
' Base Class
Public Class Users
Public Overridable Sub GetInfo()
Console.WriteLine("Base Class")
End Sub
End Class
'Derived Class
Public Class Details
Inherits Users
Public Overrides Sub GetInfo()
Console.WriteLine("Derived Class")
End Sub
End Class
If you observe the above code snippet, we created two classes (“Users”, “Details”) and the derived class (Details) is inheriting the properties from the base class (Users) and we are overriding the base class method GetInfo in the derived class by creating a method with same name and parameters, this is called a method overriding in visual basic.
Here, we defined the GetInfo method with an Overridable keyword in the base class to allow derived class to override that method using the Overrides keyword.
As discussed, only the methods with Overridable keyword in the base class are allowed to override in the derived class using Overrides keyword.
Following is the example of implementing a method overriding in a visual basic programming language.
Module Module1
Public Class BClass
Public Overridable Sub GetInfo()
Console.WriteLine("Learn C# Tutorial")
End Sub
End Class
Public Class DClass
Inherits BClass
Public Overrides Sub GetInfo()
Console.WriteLine("Welcome to Tutlane")
End Sub
End Class
Sub Main(ByVal args As String())
Dim d As DClass = New DClass()
d.GetInfo()
Dim b As BClass = New BClass()
b.GetInfo()
Console.WriteLine("Press Enter Key to Exit..")
Console.ReadLine()
End Sub
End Module
When we execute the above visual basic program, we will get the result as shown below.
This is how we can achieve the method overriding in visual basic to override a base class method in child class by defining a method with the same name and signatures based on our requirements.
The following are the difference between method overloading and method overriding in a visual basic programming language.
| Type | Description |
|---|---|
| Method Overloading | Method Overloading means defining multiple methods with the same name but with different parameters. |
| Method Overriding | Method Overriding means override a base class method in the derived class by creating a method with the same name and parameters using virtual and override keywords. |