// voor
billingEngine.PIEDS["VCS"] = "+++604/3557/70761+++";
double d = Convert.ToDouble(billingEngine.PIEDS["TOT_TTC_DV"]);
// na
billingEngine.PiedsVRecord.VCS = "+++604/3557/70761+++";
double d = billingEngine.PiedsVRecord.TOT_TTC_DV;