在asp.net中导出为ex​​cel的date问题

protected void ExportToExcel(object sender, EventArgs e) { Response.ClearContent(); Response.AddHeader("content-disposition", "attachment;filename=Detail.xls"); Response.ContentType = "application/excel"; StringWriter sw = new StringWriter(); HtmlTextWriter htm = new HtmlTextWriter(sw); Repeater repAllUsers = this.rptrRegistrationReport; repAllUsers.DataSource = objAdmin.Getregdetails(start, enddate, usrtype); repAllUsers.DataBind(); repAllUsers.RenderControl(htm); Response.Write("<Table border='1'" + "cellSpacing='0' cellPadding='0' " +"style='font-size:12.0pt; '>"); Response.Write(sw.ToString()); Response.End(); } 

所有的数据都输出正确，但只有date栏显示#####如何在Excel文件中显示date。