private void button4_Click(object sender, EventArgs e) { var fly = new MsSql(new ConnectionStringModel(_sqlIp, _db, _sqlUser, _sqlPass)); var dataTable = fly.ExecStoredProcedure("CofA_Prod", "Test3", "dupa", "dupa"); rTB.AppendText(dataTable.Rows[0][0].ToString()); }