Avalonia/src/Avalonia.Dialogs/InternalViewModelBase.cs

using System.Collections.Generic;
using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace Avalonia.Dialogs.Internal
{
    public class InternalViewModelBase : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        protected bool RaiseAndSetIfChanged<T>(ref T field, T value, [CallerMemberName] string propertyName = null)
        {
            if (!EqualityComparer<T>.Default.Equals(field, value))
            {
                field = value;
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
                return true;
            }

            return false;
        }

        protected void RaisePropertyChanged([CallerMemberName] string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}