[FormControlEventHandler(formControlStr(SystemParameters, ARTaxParametersGrid_TaxGroup), FormControlEventType::Lookup)]
public static void ARTaxParametersGrid_TaxGroup_OnLookup(FormControl sender, FormControlEventArgs e)
{
SysTableLookup sysTableLookup = SysTableLookup::newParameters(tableNum(TaxGroupHeading),sender);
Query query = new Query();
IntARTaxParameters arTaxParm = sender.formRun().dataSource(formDataSourceStr(SystemParameters,IntARTaxParameters)).cursor();
QueryBuildDataSource qbdsTaxGroupHeading = query.addDataSource(tableNum(TaxGroupHeading));
qbdsTaxGroupHeading.company(strFmt(arTaxParm.LegalEntityDataAreaId));
qbdsTaxGroupHeading.relations(true);
qbdsTaxGroupHeading.addRange(fieldNum(TaxGroupHeading,DataAreaId)).value(arTaxParm.LegalEntityDataAreaId);
sysTableLookup.addLookupfield(fieldNum(TaxGroupHeading,TaxGroup));
sysTableLookup.parmQuery(query);
sysTableLookup.performFormLookup();
FormControlCancelableSuperEventArgs ce = e as FormControlCancelableSuperEventArgs;
//cancel super() to prevent error.
ce.CancelSuperCall();
}


