---

private void btnDelete_Click(
    object sender,
    EventArgs e)
{
    if (dgvProducts.SelectedRows.Count > 0)
    {
        int id = Convert.ToInt32(
            dgvProducts.SelectedRows[0]
            .Cells["Id"].Value);

        using (SQLiteConnection connection =
            new SQLiteConnection(connectionString))
        {
            connection.Open();

            string sql =
                "DELETE FROM Products WHERE Id=@id";

            SQLiteCommand command =
                new SQLiteCommand(sql, connection);

            command.Parameters.AddWithValue(
                "@id",
                id);

            command.ExecuteNonQuery();

            MessageBox.Show(
                "Товар удален");

            LoadProducts();
        }
    }
    else
    {
        MessageBox.Show(
            "Выберите товар для удаления");
    }
}