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protected void Page_Load(object sender, EventArgs e)
    {

        ViewState["Historty"] = Convert.ToInt32(ViewState["Historty"]) + 1;

        if (!IsPostBack)
        {
            ViewState["Historty"] = 1;
        }

    }
    protected void ImageButton1_Click(object sender, ImageClickEventArgs e)
    {
        Response.Write("");
    }