Can we store the filepath temporarily in the codebehind converting from rdcl file to pdf

protected void btnDownload_Click(object sender, EventArgs e)
        {
                 string contentType = string.Empty;  
                if (ddlFileFormat.SelectedValue.Equals(".pdf"))  
                    contentType = "application/pdf";  
                if (ddlFileFormat.SelectedValue.Equals(".doc"))  
                    contentType = "application/ms-word";  
                if (ddlFileFormat.SelectedValue.Equals(".xls"))  
                    contentType = "application/xls";
                string empid = Session["Empid"].ToString();
                DataTable dsData = new DataTable();
                objOldIncBOL.EmpId = Session["Empid"].ToString();
                dsData = objOldIncBLL.getdata(objOldIncBOL);     
                string FileName = "File_" + DateTime.Now.ToString("ddMMyyyyhhmmss") + ddlFileFormat.SelectedValue;  
                string extension;  
                string encoding;  
                string mimeType;  
                string[] streams;  
                Warning[] warnings;    
                LocalReport report = new LocalReport();
                report.ReportPath = Server.MapPath("~\\UI\\OldRecords\\OldIncrementReport.rdlc");  
                ReportDataSource rds = new ReportDataSource();
                rds.Name = "OldIncrementReport";//This refers to the dataset name in the RDLC file  
                rds.Value = dsData;  
                report.DataSources.Add(rds);
                Byte[] mybytes = report.Render(ddlFileFormat.SelectedItem.Text, null,  
                                out extension, out encoding,  
                                out mimeType, out streams, out warnings); 
            //for exporting to PDF

                var a = mybytes;
               
                using (FileStream fs = File.Create(Server.MapPath("~/download/") + FileName))  
                {  
                     fs.Write(mybytes, 0, mybytes.Length);
                    
                }

                string fileNames = System.IO.Path.GetTempPath() + Guid.NewGuid().ToString() + ddlFileFormat.SelectedValue;

                //fileattch.InnerText = ;
                //string fileName = this.Id.ToString() + extension;
                //switch (AppConfiguration.DataStoreType)
                //{
                //    case DataStoreType.Database:
                //        myFile.Save();
                //        break;
                //    case DataStoreType.FileSystem:
                //        myFile.Save(Server.MapPath(Path.Combine(
                //        AppConfiguration.UploadsFolder, myFile.FileUrl)));
                //        break;
                //}
               

                Response.ClearHeaders();  
                Response.ClearContent();  
                Response.Buffer = true;  
                Response.Clear();  
                Response.ContentType = contentType;  
                Response.AddHeader("Content-Disposition", "attachment; filename=" + FileName);  
                Response.WriteFile(Server.MapPath("~/download/" + FileName));
                Response.BinaryWrite(mybytes);
                Response.Flush();  
                Response.Close();  
                Response.End();


        }