using ReactiveUI; using System; namespace BindingDemo.ViewModels { public class ExceptionErrorViewModel : ReactiveObject { private int _lessThan10; public int LessThan10 { get { return _lessThan10; } set { if (value < 10) { this.RaiseAndSetIfChanged(ref _lessThan10, value); } else { throw new ArgumentOutOfRangeException(nameof(value), "Value must be less than 10."); } } } } }