private void cmdSave_Click(object sender, EventArgs e)
{
    try
    {
        con = new OleDbConnection(cs.DBConn);
        con.Open();

        string queryInsert = @"INSERT INTO tblFixing(CodBefore)
                               VALUES
                               (@CodBefore)";
        cmd = new OleDbCommand(queryInsert);
        cmd.Connection = con;

        cmd.Parameters.Add(new OleDbParameter("@CodBefore", OleDbType.WChar, 0, "CodBefore"));

        cmd.Parameters["@CodBefore"].Value = rchCodBefore.Text.Trim();

        cmd.ExecuteNonQuery();
        MessageBox.Show("Successfully saved", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
        cmdSave.Enabled = false;

        con.Close();
    }
    catch (Exception ex)
    {
        MessageBox.Show("ErrornDetalhes: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
    }
}