asp.net上传execl文件后,在页面上加载显示(示例代码)

    #region 上传execl文件
    protected void button1_click(object sender, eventargs e)
    {
        if (fileupload1.hasfile)
        {
            string newfilename = string.empty;
            string errormess = uploadfile(fileupload1, ".xls|.xlsx", 1024 * 5, server.mappath("/report/socialapply/"), 1, out newfilename);
            if (string.isnullorempty(errormess))
            {
                label1.text = "√文件上传成功";
                viewstate["uploadfile"] = "/report/socialapply/" + newfilename;
                try
                {
                    filestream file = new filestream
                        (server.mappath(viewstate["uploadfile"] as string),
                        filemode.open, fileaccess.read,
                        fileshare.readwrite);
                    datatable dt1 = fairhr.util.xmlexcelreport.readexceltodatatable(file, 0, 0);

                    viewstate.add("viewdt", dt1);
                    gridview1.datasource = viewstate["viewdt"] as datatable;
                    gridview1.databind();
                    file.close();
                    //maticsoft.common.messagebox.responsescript(page, "$.messager.alert('系统提示', '操作成功！', 'info');");
                }
                catch
                {
                    maticsoft.common.messagebox.responsescript(page, "$.messager.alert('系统提示', '请重新上传execl文件再操作', 'warning');");
                }
            }
            else
            {
                label1.text = "×文件上传失败";
            }
        }
        else
        {
            label1.text = "×请先选择上传文件";
        }
        scriptmanager.registerclientscriptblock(page, this.gettype(), "idalert1", "closeload();", true);
    }
    #endregion

    #region 上传文件
    /// <summary>
    /// 上传文件
    /// </summary>
    /// <param name="fu">上传文件</param>
    /// <param name="type">上传文件类型,例如.jpg|.gif|.bmp</param>
    /// <param name="size">限制上传文件大小，单位为k</param>
    /// <param name="path">上传路径，需使用server.mappath</param>
    /// <param name="nametype">1为自动命名,0用原名</param>
    /// <returns></returns>
    public static string uploadfile(fileupload fu, string type, int size, string path, int nametype, out string newfilename)
    {
        newfilename = null;
        string erorr = null;
        int size = fu.postedfile.contentlength / 1024;
        if (size > size)
        {
            erorr = "上传文件太大！";
            return erorr;
        }
        string type = fu.filename;
        if (type.indexof(".") == -1) { erorr = "上传文件类型有误！"; return erorr; }
        type = type.substring(type.lastindexof(".")).toupper();
        type = type.toupper();
        if (type.indexof(type) == -1) { erorr = "上传文件类型有误！"; return erorr; }

        string filename = "";
        if (nametype == 1)
        {
            string nowdate = datetime.now.tostring();
            nowdate = nowdate.replace(":", "").replace(" ", "").replace("-", "").trim();
            random r = new random();
            int a = r.next(1000);
            filename = nowdate + a.tostring() + type;
            newfilename = filename;
        }
        else
        {
            filename = fu.filename;
            if (system.io.file.exists(path + filename)) { erorr = "此文件名已经存在！"; return erorr; }
        }

        fu.saveas(path + filename);
        return erorr;//返回有错的错误信息，没有错误返回null
    }
    #endregion