public void GetClientIdAndContractId()
        {
            var        distinctClientId = ClientList.GroupBy(x => x.ClientId).Select(y => y.First());
            List <int> clientIdList     = new List <int>();

            foreach (var clientId in distinctClientId)
            {
                clientIdList.Add(clientId.ClientId);
            }

            DistinctClientIdList = clientIdList;

            int selectedClientId = clientIdList[_clientIndex];

            List <int> contractIdList = new List <int>();

            foreach (var contractId in ClientList.Where(x => x.ClientId == selectedClientId))
            {
                contractIdList.Add(contractId.ContractId);
            }

            SelectedClientId   = selectedClientId;
            ContractIdList     = contractIdList;
            SelectedContractId = ContractIdList[ContractIndex];
        }