BindableBase vs INotifyChanged

INotifyPropertyChanged

The ViewModel should implement the INotifyPropertyChanged interface and should raise it whenever the propertychanges

public class MyViewModel : INotifyPropertyChanged
{
    private string _firstName;


    public event PropertyChangedEventHandler PropertyChanged;

    public string FirstName
    {
        get { return _firstName; }
        set
        {
            if (_firstName == value)
                return;

            _firstName = value;
            PropertyChanged(this, new PropertyChangedEventArgs("FirstName"));
        }
    }


    }
}

Problem is with ICommand interface as most of the code is duplicated also since it passes string it becomes error prone.

Whereas Bindablebase is an abstract class that implements INotifyPropertyChanged interface and provide SetProperty<T>.You can reduce the set method to just one line also ref parameter allows you to update its value. The BindableBase code below comes from INotifyPropertyChanged, The .NET 4.5 Way – Revisited

   public class MyViewModel : BindableBase
{
    private string _firstName;
    private string _lastName;

    public string FirstName
    {
        get { return _firstName; }
        set { SetProperty(ref _firstName, value); }
    }


}

     //Inside Bindable Base
    public abstract class BindableBase : INotifyPropertyChanged
    {

       public event PropertyChangedEventHandler PropertyChanged;

       protected bool SetProperty<T>(ref T storage, T value, [CallerMemberName] String propertyName = null)
       {
          if (Equals(storage, value))
          {
             return false;
          }

          storage = value;
          this.OnPropertyChanged(propertyName);
          return true;
       }

    protected void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
      PropertyChangedEventHandler eventHandler = this.PropertyChanged;
      if (eventHandler != null)
      {
          eventHandler(this, new PropertyChangedEventArgs(propertyName));
      }
    }
}