[Persistent] attribute that automatically saves/loads properties with PlayerPrefs

PersistentSROptions.cs

using UnityEngine;
using System;
using System.Reflection;
using Helios;

//this creates the [Persistent] attribute that can be applied before a property
[AttributeUsage(AttributeTargets.Property)]
public class PersistentAttribute : Attribute
{
}


public class PersistentSROptions {

	// Use this for initialization
	public PersistentSROptions ()
	{
	    SROptions.Current.PropertyChanged += OnSROptionsPropertyChanged;
        InitializePersistent();
	}

    //if property is marked [Persistent] and is set, this will save its value to playerprefs
    private void OnSROptionsPropertyChanged(object sender, string propertyname)
    {
        PropertyInfo property = sender.GetType().GetProperty(propertyname);

        if(property != null && !Attribute.IsDefined(property, typeof(PersistentAttribute)))
            return;
        
        //currently only supports floats. no reason this check cant be expanded. maybe best to use a generic delegate
        if (property.PropertyType == typeof(Single))
        {
            ExternalConfig.SetKey(propertyname, (float)property.GetValue(sender, null));
        }
    }

    //finds all properties marked [Persistent] and loads them from playerprefs if a key is there.
    public void InitializePersistent()
    {
        Type objtype = SROptions.Current.GetType();
        foreach (var propertyInfo in objtype.GetProperties())
        {
            foreach (var customAttribute in propertyInfo.GetCustomAttributes(typeof(PersistentAttribute), false))
            {
                PersistentAttribute persistent = (PersistentAttribute)customAttribute;
                UnityEngine.Debug.Log(propertyInfo.Name + " is marked as persistent");

                //currently only supports floats. no reason this check cant be expanded. maybe best to use a generic delegate
                if (propertyInfo.PropertyType == typeof(System.Single))
                {
                    if(ExternalConfig.HasKey(propertyInfo.Name))
                        propertyInfo.SetValue(
                            SROptions.Current,
                            (float)ExternalConfig.GetKey(propertyInfo.Name, 0),
                            null
                        );
                }
            }
        }
    }
}

make sure to construct the class. I do it in my Zenject installer.

Also add this method to ExternalConfig

public static bool HasKey(string keyName) { JToken keyToken = _configData[keyName]; return keyToken != null; }