C#下载csv代码总结

一、C#导出csv格式代码如下：

        /// <summary>
        /// 下载
        /// </summary>
        /// <param name="startTime"></param>
        /// <param name="endTime"></param>
        public void Download(DateTime? startTime, DateTime? endTime)
        {
            Response<VSysLog> _rsp = new Response<VSysLog>();
            try
            {
                using (NetEntities et = new NetEntities())
                {
                    startTime = startTime == null ? DateTime.Now.AddMonths(-2) : startTime.Value;
                    endTime = endTime == null ? DateTime.Now : endTime.Value;
                    int deviceType = (int)EnumDeviceType.网关设备;

                    //搜索条件
                    var whereQuery = PredicateExtensions.True<net_warninglog>();
                    //搜索条件---开始时间和结束时间
                    whereQuery = whereQuery.And(n => n.WarningTime >= startTime && n.WarningTime <= endTime);
                    //搜索条件---设备类型
                    whereQuery = whereQuery.And(n => n.DeviecType == deviceType);
                    //搜索条件---模糊查询
                    if (!string.IsNullOrEmpty(Request["condition"]))
                    {
                        string condition = Request["condition"];
                        whereQuery = whereQuery.And(n => n.WarningSource.Contains(condition));
                    }
                    List<VWarningLog> logList = et.net_warninglog.Where(whereQuery.Compile()).AsEnumerable().Select(n =>
                                          new VWarningLog
                                          {
                                              id = n.ID,
                                              warningName = n.WarningName,
                                              warningReason = n.WarningReason,
                                              deviceType = Enum.GetName(typeof(EnumDeviceType), n.DeviecType),
                                              warningSource = n.WarningSource,
                                              descr = n.Descr,
                                              warningTime = n.WarningTime.ToString("yyyy-MM-dd HH:mm:ss")
                                          }).OrderByDescending(x => x.warningTime).ToList();

                    System.IO.StringWriter sw = new StringWriter();
                    StringBuilder sbTitle = new StringBuilder();
                    System.Web.HttpResponse response = System.Web.HttpContext.Current.Response;
                    //定义模版（标题、内容字段、格式化参数）
                    string[,] template = new string[,] {{ "终端编号,", "warningSource", "{0}"}, { "设备类型,", "deviceType", "{0}" }, { "报警原因,", "warningReason", "{0}"},
                                                                        { "报警信息,", "warningName", "{0}" }, { "描述", "descr", "{0}" }, { "报警时间", "warningTime", "{0}" } };
                    string strLine = "";
                    sw = new StringWriter();
                    //获取模板的行数
                    int colCount = template.GetLength(0);
                    //表头    
                    for (int i = 0; i < colCount; i++)
                    {
                        //在模板里面已经添加了逗号
                        strLine += template[i, 0];
                    }
                    strLine.Remove(strLine.Length - 1);
                    sw.WriteLine(strLine);
                    strLine = "";

                    //表的内容  
                    for (int j = 0; j < logList.Count; j++)
                    {
                        strLine = "";
                        for (int k = 0; k < colCount; k++)
                        {
                            if (k > 0 && k < colCount)
                            {
                                strLine += ",";
                            }
                            string cell = "";
                            string data = string.Format(template[k, 2], logList[j].GetType().GetProperty(template[k, 1]).GetValue(logList[j], null));
                            if (string.IsNullOrEmpty(data))
                            {
                                strLine += "";
                            }
                            else
                            {
                                //前面加的单引号则是防止数字被转换成其它格式    
                                cell = "'" + data.Trim();
                            }
                            //防止里面含有特殊符号
                            if (!string.IsNullOrEmpty(cell))
                            {
                                cell = cell.Replace(""", """");
                                cell = """ + cell + """;
                                strLine += cell;
                            }
                        }
                        sw.WriteLine(strLine);
                    }
                    string attachment = "attachment; filename=" + DateTime.Now.ToString("yyyy年MM月dd日HH点") + "网关报警日志.csv";
                    Response.Clear();
                    Response.ClearHeaders();
                    Response.ClearContent();
                    Response.AddHeader("content-disposition", attachment);
                    Response.ContentType = "text/csv";
                    Response.AddHeader("Pragma", "public");
                    Response.Charset = "UTF-8";
                    Response.ContentEncoding = System.Text.Encoding.UTF8;
                    Response.HeaderEncoding = System.Text.Encoding.UTF8;
                    //防止中文乱码  
                    Response.BinaryWrite(new byte[] { 0xEF, 0xBB, 0xBF });
                    response.Write(sw.ToString());
                    Response.End();
                    sw.Close();
                }
            }
            catch (Exception ex)
            {
                _rsp.code = (int)EnumCode.程序异常;
                _rsp.msg = ex.Message;
                LogHelper.WriteLog(className, "Download", ex);
            }
        }

仅作为保存，方便日后查看代码。