<PackageReference Include="System.Reactive" Version="4.1.4" />

Disposable

public static class Disposable
Provides a set of static methods for creating IDisposable objects.
namespace System.Reactive.Concurrency { public interface IScheduler { DateTimeOffset Now { get; } IDisposable Schedule<TState>(TState state, Func<IScheduler, TState, IDisposable> action); IDisposable Schedule<TState>(TState state, TimeSpan dueTime, Func<IScheduler, TState, IDisposable> action); IDisposable Schedule<TState>(TState state, DateTimeOffset dueTime, Func<IScheduler, TState, IDisposable> action); } }