字段名带 # 符号，Model 层无法addr##1,所以使用addr1，然后查询的时候使用别名，即可解决

public class VendaddrMst
    {
        public string vend_num { get; set; }
        public string name { get; set; }
        public string internal_email_addr { get; set; }
        public string external_email_addr { get; set; }
        public string contact { get; set; }
        public string phone { get; set; }
        public string city { get; set; }
        public string state { get; set; }
        public string zip { get; set; }
        public string addr1 { get; set; }
        public string addr2 { get; set; }
    }

private List<VendaddrMst> getListVendaddrMst()
        {
            string sSql = @"SELECT 
                                    M.vend_num,
                                    M.name,
                                    M.internal_email_addr,
                                    M.external_email_addr,
                                    V.contact,
                                    V.phone,
                                    M.city, 
                                    M.state, 
                                    M.zip, 
                                    M.addr##1 addr1, 
                                    M.addr##2 addr2
                                    FROM vendaddr_mst M
                                    LEFT JOIN vendor_mst V ON (M.vend_num = V.vend_num)";
            using (SqlConnection conn = new SqlConnection(_jmp_app_ConnectionString))
            {
                var ItemVendaddrMst = conn.Query<VendaddrMst>(sSql);

                if (ItemVendaddrMst == null)
                {
                    return null;
                }

                var itemMstAllList = ItemVendaddrMst.AsList();

                return itemMstAllList;
            }
        }