procedure TForm1.Button1Click(Sender: TObject); var dOPCEventServer: TdOPCEventServer; Source, ConditionName: string; ConditionNames : TStringlist; Condition : TdOPCEventCondition; begin ConditionNames := TStringlist.Create; Source := 'Device1.Ramp'; dOPCEventServer.QuerySourceConditions(Source,ConditionNames); if ConditionNames.Count > 0 then begin ConditionName := ConditionNames[0]; Condition := dOPCEventServer.GetConditionState(Source,ConditionName); if Condition <> nil then begin //... show info ... Condition.Free; end; end; ConditionNames.Free; end;