上传文件带超连接并计算个数

     protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                Session["demo"] = new List<String>();
            }
        }
        private static int f;//给全局变量并赋值0，static可以保存值
      
     

        protected void Button1_Click(object sender, EventArgs e)
        {
              string FileName = FileUpload2.PostedFile.FileName;
              if (FileName == "")
              {
                  Page.ClientScript.RegisterClientScriptBlock(this.GetType(), Guid.NewGuid().ToString(), string.Format("<script>alert(‘上传文件不能为空!‘)</script>"));
              }
              else
              {
                  string file_KB = FileUpload2.PostedFile.ContentLength.ToString() + "KB<br>";//获取文件大小
                  string file = FileUpload2.FileName;//获取上传文件名字

                  string URL = "http://amid01110/456/" + file + " ";


                  List<string> list = Session["demo"] as List<string>;
                  Session["demo"] = list;
                  string lntext = "<a  href=‘" + URL + "‘  >" + file + "</a>" + "大小" + file_KB + "上传文件成功";



                  Label1.Text += Label1.Text.Length > 0 ? "<br />" + lntext : lntext;
                  f++;//添加的个数
                  Label2.Text = f.ToString();
              }
        }

  <div>
    <asp:FileUpload ID="FileUpload2" runat="server" />
    <asp:Button ID="Button3" runat="server" Text="Button" OnClick="Button1_Click" />
    共上传<asp:Label ID="Label2" runat="server"></asp:Label>
    个<br />
    <asp:Label ID="Label1" runat="server" Text=""></asp:Label>
    </div>

   protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                ViewState["demo"] = 0;
            }
        }
        
      
     

        protected void Button1_Click(object sender, EventArgs e)
        {
            
              string FileName = FileUpload2.PostedFile.FileName;
              if (FileName == "")
              {
                  Page.ClientScript.RegisterClientScriptBlock(this.GetType(), Guid.NewGuid().ToString(), string.Format("<script>alert(‘上传文件不能为空!‘)</script>"));
              }
              else
              {
                  string file_KB = FileUpload2.PostedFile.ContentLength.ToString() + "KB<br>";//获取文件大小
                  string file = FileUpload2.FileName;//获取上传文件名字
                  ViewState["demo"] = Convert.ToInt32(ViewState["demo"]) + 1;//ViewState["demo"]获取个数

                  string URL = "http://amid01110/456/" + file + " ";


                 
                  string lntext = "<a  href=‘" + URL + "‘  >" + file + "</a>" + "大小" + file_KB + "上传文件成功";



                  Label1.Text += Label1.Text.Length > 0 ? "<br />" + lntext : lntext;
                 
                  Label2.Text = ViewState["demo"].ToString();
              }
        }