Components

<cat>Code.Game</cat>
<title>Components</title>

# Components

Components are bits of functionality you can add to [GameObjects](https://wiki.facepunch.com/sbox/GameObjects). You can create a component to do anything you wish. There are also numerous components that exist in the s&box engine by default. You can find a list of example components within the [sbox-scenestaging repo](https://github.com/Facepunch/sbox-scenestaging/tree/main/code/ExampleComponents) on Facepunch's GitHub.

## Properties

An attribute `[Property]` can be added to a [property member](https://learn.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/properties) on your component class, which allows you to slot in information about the property outside of code. This allows your component to be more re-usable.

```cs
public sealed class Health : Component
{
	// MaxHealth can be changed within the editor now, but defaults to 100f.
	[Property] public float MaxHealth { get; set; } = 100f;
	public float CurrentHealth { get; set; }

	protected override void OnStart()
	{
		// Set current health to max health when this component starts up
		CurrentHealth = MaxHealth;
	}
}
```

See the [Attributes and Component Properties](https://wiki.facepunch.com/sbox/Property) page for more info and examples.

## Methods

There are a number of methods you can override when making your own component. You can find a full list [here](https://docs.facepunch.com/s/sbox-dev/doc/component-methods-OCvoNh8ByW). Below is an example of overriding a method.
```cs
public sealed class MyComponent : Component
{
	// OnUpdate is called every frame
	protected override void OnUpdate()
	{
		LocalRotation = Rotation.Random;
	}
}
```

## Enabling and Disabling

You can enable or disable a component through code. When a component is disabled, methods like OnUpdate, OnFixedUpdate, and more are skipped. Whenever you enable a component, OnStart and OnEnabled will be called (in that order). Disabling a component calls OnDisabled.
```cs
var comp = Components.Get<Health>();

if ( comp.CurrentHealth <= 0 )
{
	// Will trigger OnDisabled on Health
	comp.Enabled = false;
}
```

## Managing a Component on a GameObject

Most often, you will want to add components to a GameObject outside of the codebase (through the scene editor). But sometimes, there are cases you want to add to or remove from a GameObject directly.
```cs
// Gets Health, or creates it if it does not exist.
var comp = Components.GetOrCreate<Health>();

```

From within a component, many properties of a GameObject (such as Transform, Components, Scene, etc) are exposed for you for convenience.

```cs
public sealed class MyComponent : Component
{
	protected override void OnStart()
	{
		// Changing the Transform on a Component simply adjusts the Transform of the GameObject.
		WorldPosition = new Vector3( 10f, 0f, 10f );

		if ( Components.TryGet( out Health health, FindMode.EnabledInSelfAndChildren ) )
			health.Destroy();
	}
}
```

Components

Account Management

Special Pages

Wiki List

S&box Wiki