OutWit.Common.Aspects

A lightweight runtime AOP library for automating INotifyPropertyChanged notifications in.NET.

Overview

Implementing INotifyPropertyChanged is essential for data binding in modern.NET UI frameworks like WPF, MAUI, and Avalonia, but it often leads to verbose, repetitive, and error-prone boilerplate code in your ViewModels.

OutWit.Common.Aspects solves this problem by providing a simple, runtime-based "aspect" that automatically injects property change notifications into your classes.

Install

Install-Package OutWit.Common.Aspects

or

> dotnet add package OutWit.Common.Aspects

Before:

public class MyViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler? PropertyChanged = delegate { };

    private string m_text;

    public MyViewModel()
    {
        this.PropertyChanged += OnPropertyChanged;
    }

    private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e)
    {
        if (e.PropertyName == "Text")
        {
            Trace.Write("I am here!");
        }
    }

    public string Text
    {
        get => m_text;
        set
        {
            m_text = value;
            PropertyChanged(this, new PropertyChangedEventArgs("Text"));
        }
    }
}

After:

    public class MyViewModel : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler? PropertyChanged = delegate { };

        public MyViewModel()
        {
            this.PropertyChanged += OnPropertyChanged;
        }

        private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e)
        {
            if (e.IsProperty((MyViewModel vm) => vm.Text))
            {
                Trace.Write("I am here!");
            }
        }

        [Notify]
        public string Text { get; set; }
    }

For more details, check out the article.

License

Licensed under the Apache License, Version 2.0. See .