WPF绑定 - 如何确定对象无效以防止保存

public class MyData : INotifyPropertyChanged
{
    private string _name;
    public string Name
    {
        get { return _name; }
        set
        {
            if (_name != value)
            {
                _name = value;
                OnPropertyChanged("Name");
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
    }
}

public class MyData : IDataErrorInfo
{
    public string Error
    {
        get { return null; }
    }

    public string this[string columnName]
    {
        get
        {
            string error = null;
            if (columnName == "Name")
            {
                if (string.IsNullOrEmpty(Name))
                {
                    error = "Name is required.";
                }
            }
            return error;
        }
    }
}

private void SaveData(MyData data)
{
    if (string.IsNullOrEmpty(data.Error))
    {
        // Save data
    }
    else
    {
        // Display error message
    }
}