Write a program that uses protocol extension.

Question

Accepted Answer

A protocol extension allows adding functionality to existing types without modifying their original implementation.

Define a protocol with required methods
Create an extension for the protocol
Implement the methods in the extension

Accepted Answer

public interface IPrintable

{

void Print();

}

public static class PrintableExtensions

{

public static void Print(this IPrintable printable)

{

Console.WriteLine("Printing...");

}

In this example, Print is an extension method for the IPrintable interface. It provides a default implementation for the Print method that simply prints "Printing..." to the console.

Now, you can use the protocol extension by implementing the IPrintable interface in your classes:

public class Document : IPrintable

{

public void Print()

{

Console.WriteLine("Document is being printed...");

}

public class Photo : IPrintable

{

// No explicit implementation of Print is provided here.

// The extension method from PrintableExtensions will be used.

}

Here, the Document class provides its own implementation of the Print method, while the Photo class relies on the protocol extension to provide the default implementation.

class Program

{

static void Main(string[] args)

{

Document doc = new Document();

Photo photo = new Photo();

doc.Print(); // This will use the class-specific implementation.

photo.Print(); // This will use the protocol extension's default implementation.

Console.ReadLine();

}

When you call Print on the Document object, it uses the class-specific implementation. When you call Print on the Photo object, it uses the default implementation provided by the protocol extension.

This is a basic example of how you can create a protocol extension in C# using interfaces and extension methods. You can extend this concept to add more functionality to your interfaces and classes as needed.

Write a program that uses protocol extension.

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