Template Method Design Pattern in C#

The Template Method Design Pattern is a behavioral design pattern that defines the skeleton of an algorithm in the superclass but lets subclasses override specific steps of the algorithm without changing its structure. It allows reusing common behavior across multiple classes while still allowing customization where necessary.

Components of Template Method Design Pattern

• Abstract Class: This class defines the template method, which is the skeleton of the algorithm. It consists of several abstract methods that subclasses must implement.
• Concrete Classes: These classes inherit from the abstract class and provide implementations for the abstract methods.

Command Design Pattern in C#

The Command Design Pattern is a behavioral design pattern that encapsulates a request as an object, thereby allowing parameterization of clients with queues, requests, and operations. This pattern decouples sender and receiver of a request based on a command, which helps in invoking the right method at the right time without knowing the actual implementation details.

Components of Command Design Pattern

1. Command: Defines an interface for executing an operation.
2. Concrete Command: Implements the Command interface and binds a receiver with an action. It defines a binding between the action and the receiver.
3. Invoker: Requests the command to execute the operation.
4. Receiver: Knows how to perform the operation.

Strategy Design Pattern in C#

The Strategy Design Pattern is a Behavioral Design Pattern that enables selecting an algorithm’s behavior at runtime. Instead of implementing a single algorithm directly, run-time instructions specify which of a family of algorithms to use.

This pattern is ideal when you need to switch between different algorithms or actions in an object dynamically. That means the Strategy Design Pattern is used when we have multiple algorithms (solutions) for a specific task, and the client decides which algorithm to use at runtime.

Components of Strategy Design Pattern

1. Strategy Interface: This defines a set of methods that represent the algorithms. It acts as a contract for all concrete strategy classes.
2. Concrete Strategies: These are the actual implementations of the algorithms defined in the strategy interface.
3. Context: This is the class that uses the strategy. It contains a reference to the strategy interface and can switch between different strategies dynamically.

Observer Design Pattern in C#

The Observer Design Pattern is a behavioral design pattern that defines a one-to-many dependency between objects. When one object (the subject) changes its state, all its dependents (observers) are notified and updated automatically. This pattern is widely used in software engineering to establish communication between objects in a loosely coupled manner.

This Design Pattern is widely used for implementing distributed event-handling systems where an object needs to notify other objects about its state changes without knowing who these objects are.

In the Observer Design Pattern, an object (called a Subject) maintains a list of its dependents (called Observers). It notifies them automatically whenever any state changes by calling one of their methods. The Other names of this pattern are Producer/Consumer and Publish/Subscribe.

Components of Bridge Design Pattern

1. Subject: This is the object that is being observed. It maintains a list of observers and provides methods to attach, detach, and notify observers of state changes.
2. Observer: This is the interface that defines the method(s) that the subject will use to notify observers of state changes.
3. ConcreteSubject: This is the concrete implementation of the subject. It maintains the state of interest and notifies observers when changes occur.
4. ConcreteObserver: This is the concrete implementation of the observer. It registers itself with the subject and implements the update method to react to changes in the subject's state.

Standalone Components in Angular

A standalone component is a type of component that doesn’t belong to any specific Angular module.Before Angular version 14, when you created a component, you typically had to include it in the declaration array of a module; otherwise, Angular would throw an error during compilation.Standalone components are independent units that can be instantiated and used anywhere within an Angular application, regardless of the module structure. Standalone components can be useful for creating reusable UI elements or utility functions that are not specific to any module.

In this post, we'll explore standalone components in Angular and how to create them with a detailed example.

Creating a Standalone Component

First, make sure you're using Angular version 14. To create a component on its own, use the --standalone option with the command ng generate component.

ng g c component_name  --standalone