上载多个文档

请问要怎样修改才能上载多个文档 private void FileUpload(string fileurl, string filename, string strGuid)
        {
            SPSecurity.RunWithElevatedPrivileges(delegate()//模仿管理员的权限进行操作（代码访问权限提升）
            {
                using (SPSite site = new SPSite(SPContext.Current.Site.ID))//实例化SPWeb对象才能保证执行者是管理员
                {
                    site.AllowUnsafeUpdates = true;
                    using (SPWeb web = site.AllWebs[SPContext.Current.Web.ID])
                    {
                        web.AllowUnsafeUpdates = true;                        string Path = @"D:\Folder\" + filename;
                        this.FileUpload1.SaveAs(Path);
                        fileurl = Path;
                        SPList Mylist = web.Lists["项目申请"];
                        FileStream fstream = File.OpenRead(fileurl);//以文件流的形式读取文件源
                        byte[] contens = new byte[fstream.Length];//定义一个直接数组
                        fstream.Read(contens, 0, (int)fstream.Length);//把文件源写入到数组容器
                        fstream.Close();//关闭文件流  
                        String url = "";
                        SPQuery query = new SPQuery();
                        query.Query = @"<Where><Eq><FieldRef Name='sGUID'/><Value Type='Text'>" + strGuid + @"</Value></Eq>
                                                    </Where>";
                        SPListItemCollection myItems = Mylist.GetItems(query);
                        //SPListItemCollection myItems = Mylist.Items;
                        foreach (SPListItem item in myItems)
                        {
                            string psGuid = item["sGUID"].ToString();
                            if (psGuid == strGuid)
                            {
                                if (item.Attachments.Count > 0)
                                {
                                    Response.Write("<script language=javascript>alert('该申请文档已经提交，请不要重复提交！')</script>");
                                }
                                else
                                {
                                    SPAttachmentCollection attach = item.Attachments;
                                    url = attach.UrlPrefix;
                                    attach.Add(filename, contens);
                                    item.Update();
                                    File.Delete(Path);
                                                                    }
                                break;
                            }
                        }                                            }
                }
            });
        }