🧩 What is the Command Pattern?

The Command Pattern is a way to turn a request (like pressing a button) into an object. This lets you store, pass, and undo commands easily.

Think of a TV remote. Each button (like Power or Volume Up) sends a command to the TV. The remote doesn't care how the TV works—it just sends a signal.

🛠 Real Life Example

Imagine a smart home app. You can tap a button to turn on the lights, start the coffee maker, or lock the doors. Each of these actions is a "command" you can send.

✅ Pros (Why use it?)

• Easy to undo actions – You can save commands and undo them later.
• Loose coupling – The button doesn't need to know how the light turns on.
• Flexibility – You can queue, log, or even delay commands.

❌ Cons (Things to watch out for)

• More code – You'll need to make a new class for each command.
• Can feel overkill for small projects.

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🧪 Let's Build It in C#

Step 1: Make a Command Interface

public interface ICommand
{
    void Execute();
    void Undo();
}

Step 2: Create a Receiver (the thing that does the work)

public class Light
{
    public void TurnOn() => Console.WriteLine("Light is ON");
    public void TurnOff() => Console.WriteLine("Light is OFF");
}

Step 3: Create Command Classes

public class LightOnCommand : ICommand
{
    private Light _light;

    public LightOnCommand(Light light)
    {
        _light = light;
    }

    public void Execute() => _light.TurnOn();

    public void Undo() => _light.TurnOff();
}

Step 4: Create the Invoker (like the remote control)

public class RemoteControl
{
    private ICommand _command;

    public void SetCommand(ICommand command)
    {
        _command = command;
    }

    public void PressButton()
    {
        _command.Execute();
    }

    public void PressUndo()
    {
        _command.Undo();
    }
}

Step 5: Use It!

class Program
{
    static void Main()
    {
        Light livingRoomLight = new Light();
        ICommand lightOn = new LightOnCommand(livingRoomLight);

        RemoteControl remote = new RemoteControl();
        remote.SetCommand(lightOn);

        remote.PressButton();  // Light is ON
        remote.PressUndo();    // Light is OFF
    }
}

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🧠 Summary

Concept	Description
Command	Object that does a task (like turn on light)
Receiver	Knows how to do the task (like the Light)
Invoker	Asks the command to run (like the Remote)

The Command Pattern is great when you need buttons, menus, undo features, or to queue up actions. It helps you stay organized and flexible—just be mindful of the extra code!