private void btn_save_Click(object sender, RoutedEventArgs e)
{
if ((this.DataContext as Task).ID == 0)
{
(this.DataContext as Task).TimeCreate = DateTime.Now;
taskContract.AddTask(this.DataContext as Task);
}
else
{
taskContract.UpdateTask(this.DataContext as Task);
}
EditEnd?.Invoke();
}
