Bytesize Gamedev #5 - [SerializeField] and [field:SerializeField]

Do your scripts have a lot of variables that you need to modify in the Inspector, but you want to keep private in your scripts? Read on!

Bytesize Gamedev is a series of shorter game development tutorials.

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Let’s start with a tiny example script.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Player : MonoBehaviour
{
    private int maxHealth;

    public int Health { get; private set; }

    public void GetHit(int damage)
    {
        Health -= damage;

        // Do other things here.
    }
}

Some of you might not use C# properties, so let’s break this down. maxHealth is a standard variable, and Health is a property - we’re using special syntax here to say we can get its value from other scripts, but we can only set its value within this script. This one is called an auto-implemented property because it creates its backing field automatically. There’s more about properties on Microsoft’s website if some of that went over your head, but we’re here to talk about how to use them in Unity.

As we know, private fields won’t appear in the Unity Inspector, but we can add an attribute called [SerializeField] to keep it private while forcing Unity to display it. Let’s stick that on both Health and maxHealth.

[SerializeField]
private int maxHealth;

[SerializeField]
public int Health { get; private set; }

Perfect if you need to keep things private in scripts but you need to set values in the Editor.

Now we can set the value of maxHealth inside Unity. But what about Health? Despite using [SerializeField], we don’t see it here. We need to use a slightly different attribute here called [field:SerializeField].

[field:SerializeField]
public int Health { get; private set; }

Not many people know you can do this!

Et voila - now we can expose auto-implemented properties in the Inspector! Only later versions of Unity make the name look pretty, and I’m unsure exactly when this was added - but it’s an invaluable bit of information.

Thanks for reading Bytesize Gamedev, your one-stop shop for shorter game development tips, tricks and tutorials!