static class GeneralClass
    {
        public static SalesManagerWcfServiceNS.SalesManagerWcfServiceClient SalesManagerWcfClient;
    }

cachetable=GeneralClass.SalesManagerWcfClient.GetData();

public class SalesManagerWcfService : ISalesManagerWcfService
    {
        GeneralQuery genQuery;

        

        public string GetData(int value)
        {
            ...
        }

       

        public int GetRowCountInvoiceJournal()
        {
            ...
        }

    }


class GeneralQuery
    {
        public enum GeneralQueriesTypes
        {
            InvoiceList
        }

        private JournalFilterClass filter;
        private GeneralQueriesTypes queryType;
        private StringBuilder query;
        private string rowCountQuery;
        private string querySelect;
        private string queryFrom;
        private string queryWhere;
        private string queryOrderBy;

......

public GeneralQuery(GeneralQueriesTypes tip,JournalFilterClass filter)
        {
            this.filter=filter;
            queryType = tip;
            ChangeQueries();
        }

...........

public override string ToString()
        {
            return this.query.ToString();
        }
}