private void btnnew_Click(object sender, RoutedEventArgs e)
        {
            Post          post   = new Post();
            WindowAddPost window = new WindowAddPost(post);

            if (window.ShowDialog() == true)
            {
                if (MinPay != null)
                {
                    post.Pay = Math.Round((double)(post.Koef * MinPay), 2);
                }
                list.Add(new PostView(post));
                post.Save();
            }
        }
        private void btnEditing_Click(object sender, RoutedEventArgs e)
        {
            if (DGLavozimlist.SelectedItem == null)
            {
                return;
            }
            WindowAddPost window = new WindowAddPost(list[DGLavozimlist.SelectedIndex].Post);

            if (window.ShowDialog() == true)
            {
                if (MinPay != null)
                {
                    list[DGLavozimlist.SelectedIndex].Post.Pay = Math.Round((double)(list[DGLavozimlist.SelectedIndex].Post.Koef * MinPay), 2);
                }
                list[DGLavozimlist.SelectedIndex].Post.Update();
            }
        }