.aspx代码如下：

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="multiUpload.aspx.cs" Inherits="upfiles_multiUpload" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <script src="../JS/jquery-1.9.1.js" type="text/javascript"></script>
    <script type ="text/javascript">
        $(document).ready(function () {
            $("#fup1").val("");
            $("#img_upload").click(function () {
                $("#fup1").click();
            });
            $("#fup1").change(function () {
                $("#btn_addSession").click();
            });

        });

        function datacheck() {
            var _file = document.getElementById("fup1");
            var _size = _file.files[0].size;
            if (_size > 1000000) {
                alert("文件大于1M,请重新选择!");
                return false;
            }

            var _count = $("#txt_FilesCount").val();
            if (_count >= 10) {
                alert("队列已满,完成上传后再次选择!");
                return false;
            }

            return true;

        }


    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h2>多文件上传</h2>
        <img src="../imgs/upload.png" width="32" alt="" id="img_upload" />

        <div id="div_hidden" style ="display:none;">
            <asp:FileUpload ID="fup1" runat="server" />
            <asp:Button ID="btn_addSession" runat="server" Text="Button"
             OnClientClick="return datacheck()" οnclick="btn_addSession_Click" />
            <asp:TextBox ID="txt_FilesCount" runat="server" />
        </div>

        <iframe id="ifm_1" src="i_mup_sessionList.aspx" width="100%"
        frameborder="0" ></iframe>
    </div>
    </form>
</body>
</html>

.aspx.cs代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class upfiles_multiUpload : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void btn_addSession_Click(object sender, EventArgs e)
    {
        for (int i = 0; i < 10; i++) {
            if (((HttpPostedFile[])Session["postedFiles"])[i] == null) {
                ((HttpPostedFile[])Session["postedFiles"])[i] = fup1.PostedFile;
                break;
            }
        }

        Response.Redirect(Request.RawUrl);
    }
}

asp.net多文件上传_javascript