ViewModel is a base class for all view models. It handles INotifyPropertyChanged using the C#5 caller member name attribute

gistfile1.cs

public abstract class ViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    [NotifyPropertyChangedInvocator]
    protected void RaisePropertyChanged([CallerMemberName] string propertyName = string.Empty)
    {
        if (propertyName = string.Empty)
        {
            throw new NotSupportedException("Cannot raise property changed on an empty property name. Make sure you are using the C# 5 compiler to make CallerMemberName work.")
        }
        
        var handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    protected bool SetField<T>(ref T field, T value, [CallerMemberName] string propertyName = "")
    {
        var changed = !EqualityComparer<T>.Default.Equals(field, value);
        if (changed)
        {
            field = value;
            RaisePropertyChanged(propertyName);
        }
        return changed;
    }
}