public void ProcessRequest(HttpContext context)        {            context.Response.Clear();            context.Response.Buffer = true;            //Server.UrlEncode 防止保存的文件名乱码            context.Response.AddHeader("Content-Disposition", "attachment;filename=" + context.Server.UrlEncode("消费明细" + string.Format("{0:yyyyMMddHHmmss}", System.DateTime.Now) + ".txt"));               context.Response.ContentType = "text/plain";              string message = "Hello World";            //如果导出的文件要换行，用Environment.NewLine            message += "Hello World" + Environment.NewLine;            context.Response.Write(message);            //停止页面的执行                 context.Response.End();         }