Serialize Field

Where the GetComponent based approaches automatically find the Rigidbody, this one exposes a field in the Inspector where you can manually assign it.

using UnityEngine;

public sealed class SerializeFieldExample : MonoBehaviour
    [SerializeField] private Rigidbody _Rigidbody;

    private void FixedUpdate()
        _Rigidbody.AddForce(Vector3.up * 10);

This concept is known as Dependency Injection; ths SerializeFieldExample class depends on a Rigidbody, but instead of finding or creating one, it simply indicates that it wants one and relies on another system to assign it (in this case, Unity's serialization system).


  • Fastest runtime performance - Unity deserializing the reference to set the field is faster than a script calling GetComponent on startup.
  • The Inspector shows what other components the SerializeFieldExample depends on and which one is actually being used.
  • The other components can be anywhere. The script isn't hard-coded with the assumption that the Rigidbody will be attached to the same GameObject.
  • There's less code than the Get Component Cached and Require Component approaches, but a bit more than the original Get Component approach.


Summary Description Solution
Manual Each time you add this script to an object you need to drag and drop a Rigidbody into the Inspector field. Reset Method and OnValidate Method are the same thing with the ability to automatically try to find a reference.