Name: ReactiveProperty
Author: neuecc xin9le okazuki

ReactiveProperty v9.6.0 — nugetz

public class MainPageViewModel
{
    public ReactivePropertySlim<string> Input { get; }
    public ReadOnlyReactivePropertySlim<string> Output { get; }
    public MainPageViewModel()
    {
        Input = new ReactivePropertySlim<string>("");
        Output = Input
            .Delay(TimeSpan.FromSeconds(1))
            .Select(x => x.ToUpper())
            .ObserveOnDispatcher()
            .ToReadOnlyReactivePropertySlim();
    }
}

public class AViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private string _name;
    public string Name
    {
        get => _name;
        set
        {
            _name = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Name)));

            // Update a command status
            DoSomethingCommand.RaiseCanExecuteChanged();
        }
    }

    private string _memo;
    public string Memo
    {
        get => _memo;
        set
        {
            _memo = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Memo)));

            // Update a command status
            DoSomethingCommand.RaiseCanExecuteChanged();
        }
    }

    // DelegateCommand is plane ICommand implementation.
    public DelegateCommand DoSomethingCommand { get; }

    public AViewModel()
    {
        DoSomethingCommand = new DelegateCommand(
            () => { ... },
            () => !string.IsNullOrEmpty(Name) && !string.IsNullOrEmpty(Memo)
        );
    }
}

<TextBlock Text="{Binding Name}">
<TextBlock Text="{Binding Memo}">

public class AViewModel
{
    public ValidatableReactiveProperty<string> Name { get; }
    public ValidatableReactiveProperty<string> Memo { get; }
    public ReactiveCommandSlim DoSomethingCommand { get; }

    public AViewModel()
    {
        Name = new ValidatableReactiveProperty<string>("", 
            x => string.IsNullOrEmpty(x) ? "Invalid value" : null);
        Memo = new ValidatableReactiveProperty<string>("",
            x => string.IsNullOrEmpty(x) ? "Invalid value" : null);
        DoSomethingCommand = new[]
            {
                Name.ObserveHasErrors,
                Memo.ObserveHasErrors,
            }
            .CombineLatestValuesAreAllFalse()
            .ToReactiveCommand()
            .WithSubscribe(() => { ... });
    }
}

<TextBlock Text="{Binding Name.Value}">
<TextBlock Text="{Binding Memo.Value}">

Package Id	Version and downloads	Description
ReactiveProperty		The package includes all core features.
ReactiveProperty.Core		The package includes minimum classes such as `ReactivePropertySlim<T>` and `ReadOnlyReactivePropertySlim<T>`. And this doesn't have any dependency even System.Reactive. If you don't need Rx features, then it fits.
ReactiveProperty.WPF		The package includes EventToReactiveProperty and EventToReactiveCommand for WPF. This is for .NET 6 or later and .NET Framework 4.7.2 or later.
ReactiveProperty.Blazor		The package includes validation support for EditForm component of Blazor with ReactiveProperty validation feature. This is for .NET 6.0 or later.

Package Id	Version and downloads	Description
ReactiveProperty.UWP		The package includes EventToReactiveProperty and EventToReactiveCommand for UWP.
ReactiveProperty.XamarinAndroid		The package includes many extension methods to create IObservable from events for Xamarin.Android native.
ReactiveProperty.XamariniOS		The package includes many extension methods to bind ReactiveProperty and ReactiveCommand to Xamarin.iOS native controls.

neuecc/ReactivePropertyv9.6.0

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