using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.IO;
using System.Threading.Tasks;
using Nito.AsyncEx;
using Realms;

namespace ConsoleApp3
{
    public class Program
    {
        public static async Task Main(string[] args)
        {
            ObservableCollectionTest();
            AsyncContext.Run(RealmCollectionTest);
        }

        private static void ObservableCollectionTest()
        {
            var item0 = new RealmItem { Id = 0 };
            var item1 = new RealmItem { Id = 1 };
            var item2 = new RealmItem { Id = 2 };
            // add items to collection 
            var colllection = new MyCollection(new[] { item0, item1 });

            // listen for notification
            var actions = new List<NotifyCollectionChangedAction>(5);
            colllection.CollectionChanged += (sender, eventArgs) =>
            {
                actions.Add(eventArgs.Action);
            };

            colllection.Add(item2); // Add items
            colllection.MoveItem(1, 2); // Move items
            colllection.Remove(item0); // Remove items
            colllection[1] = item2; // Replace items
            colllection.Clear(); // Reset items
            
            Console.WriteLine($"Actions for ObservableCollection: {string.Join(", ", actions)}");
        }

        private static void RealmCollectionTest()
        {
            var path = Path.Combine(Environment.CurrentDirectory, "realm.realm");
            var realm = Realm.GetInstance(new RealmConfiguration(path));

            var item0 = new RealmItem { Id = 0 };
            var item1 = new RealmItem { Id = 1 };
            var item2 = new RealmItem { Id = 2 };
            var colllection = new RealmWithCollection { Id = "col" };
            // add items to persistent cache & to collection
            realm.Write(() =>
            {
                realm.RemoveAll();
                realm.Add(item0);
                realm.Add(item1);
                realm.Add(item2);
                realm.Add(colllection);
                colllection.Items.Add(item0);
                colllection.Items.Add(item1);
            });

            // listen for notification
            var actions = new List<NotifyCollectionChangedAction>(5);
            colllection.Items.AsRealmCollection().CollectionChanged += (sender, eventArgs) =>
            {
                actions.Add(eventArgs.Action);
            };

            realm.Write(() => colllection.Items.Add(item2)); // Add items
            realm.Write(() => colllection.Items.Move(item1, 2)); // Move items
            realm.Write(() => colllection.Items.Remove(item0)); // Remove items
            realm.Write(() => colllection.Items[1] = item2); // Replace items
            realm.Write(() => colllection.Items.Clear()); // Reset items

            Console.WriteLine($"Actions for RealmCollection: {string.Join(", ", actions)}");
        }

        class MyCollection : ObservableCollection<RealmItem>
        {
            public MyCollection(IEnumerable<RealmItem> collection) : base(collection) { }
            public new void MoveItem(int oldIndex, int newIndex)
            {
                base.MoveItem(oldIndex, newIndex);
            }
        }
        public class RealmWithCollection : RealmObject
        {
            [PrimaryKey] public string Id { get; set; }
            public IList<RealmItem> Items { get; }
        }
        public class RealmItem : RealmObject
        {
            [PrimaryKey] public int Id { get; set; }
        }
    }
}

<Project Sdk="Microsoft.NET.Sdk">

    <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>net5.0</TargetFramework>
    </PropertyGroup>

    <ItemGroup>
      <PackageReference Include="BenchmarkDotNet" Version="0.13.1" />
      <PackageReference Include="Fody" Version="6.6.0">
        <PrivateAssets>all</PrivateAssets>
        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      </PackageReference>
      <PackageReference Include="Nito.AsyncEx.Context" Version="5.1.2" />
      <PackageReference Include="Realm" Version="10.9.0" />
      <PackageReference Include="Realm.Fody" Version="10.9.0">
        <PrivateAssets>all</PrivateAssets>
        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      </PackageReference>
    </ItemGroup>

</Project>

Actions for ObservableCollection: Add, Move, Remove, Replace, Reset
Actions for RealmCollection: Add, Move, Remove