C# 导出CSV功能记录下

异常问题1：
 如 机构编号  导出城CSV后，前面的四个0000不显示了，
解决办法   输出格式变为  =""
异常问题2：
PPMABAT01:/MABATAPS/usr/ma_batas >CH_INS_ID_CD='' and trans_dt='' fetch first  rows only with ur"              <
TRANS_DT TRANS_MT
-------- --------

解决：（如果要按上面的格式输出，请用下面的方式）
try
                        {
                            entityValues[i] = entityProperties[i].GetValue(entity, null);
                            sb.Append("\"" + HttpContext.Current.Server.HtmlDecode(entityValues[i].ToString().Replace("\"", "\"\"").
                                Replace("\n", Environment.NewLine).Replace("<BR>", Environment.NewLine)) + "\"");  //Replace("\"", "\"\"").
                                Replace("\n", Environment.NewLine).避免单元格内是SQL脚本情况换的问题，是由于字符串中含有双引号导致的。  HttpContext.Current.Server.HtmlDecode这句话可以不加，这里是应为在文本入库的时候被encode了 - -！
                            sb.Append(",");
                        }
                        catch
                        {
                            entityValues[i] = string.Empty;
                            sb.Append("\"" + entityValues[i].ToString() + "\"");
                            sb.Append(",");
                        }

/// <summary>
        /// 服务单导出
        /// </summary>
        public void ServiceOrderExport(string data)
        {
            StringBuilder sb = new StringBuilder();
            Type entityType = null; ;
            PropertyInfo[] entityProperties = null;
            var input = data.DeserializeObject<structServiceOrder>();
            using (var context = SRVDBHelper.DataContext)
            {
                sb.Remove(, sb.Length);
                var results = context.Usp_SRV_CheckServiceOrder(input.ServiceOrderID, input.AcceptWay,
                input.StatusCode, input.Description, input.OneLevelSortID, input.TwoLevelSortID,
                input.ThreeLevelSortID, input.AInsNO, input.ACompanyName, input.ADepartmentID,
                input.ASectionID, input.AName, input.CInsNO, input.CCompanyName, input.CDepartmentID,
                input.CSectionID, input.CreatorName, input.HInsNO, input.HCompanyName, input.HDepartmentID,
                input.HSectionID, input.HName, input.CreateDate1, input.CreateDate2,input.FinishDate1,
                input.FinishDate2,input.OverDueStatus);
                var entitys = results.ToList();
                //检查实体集合不能为空
                if (entitys == null || entitys.Count < )
                {
                    return;
                }
                //取出第一个实体的所有Propertie
                entityType = entitys[].GetType();
                entityProperties = entityType.GetProperties();
                for (int i = ; i < entityProperties.Length; i++)
                {
                    sb.Append(entityProperties[i].Name);
                    sb.Append(",");
                }
                sb.Remove(sb.Length - , );
                sb.Append("\r\n");
                //将所有entity添加到DataTable中
                foreach (object entity in entitys)
                {
                    //检查所有的的实体都为同一类型
                    if (entity.GetType() != entityType)
                    {
                        throw new Exception("要转换的集合元素类型不一致");
                    }
                    object[] entityValues = new object[entityProperties.Length];
                    for (int i = ; i < entityProperties.Length; i++)
                    {
                        try
                        {
                            entityValues[i] = entityProperties[i].GetValue(entity, null);
                            sb.Append("\"" + entityValues[i].ToString() + "\"");    解决如果列值为空的话，后面的空行不顶上来
                            sb.Append(",");
                        }
                        catch
                        {
                            entityValues[i] = string.Empty;
                            sb.Append("\"" + entityValues[i].ToString() + "\"");
                            sb.Append(",");
                        }
                    }
                    sb.Remove(sb.Length - , );
                    sb.Append("\r\n");
                }
                HttpResponse resp;
                resp = System.Web.HttpContext.Current.Response;
                resp.Charset = "GB2312";
                resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
                resp.AppendHeader("Content-Disposition", "attachment;filename=" + string.Format("{0:yyyyMMddHHmmss}", DateTime.Now) + ".csv");
                resp.Write(sb);
                resp.End();
            }
        }