.net aspx 禁止F5刷新页面重复触发按钮事件

解决方法： 
bool IsPageRefresh = false; 
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                ViewState["ViewStateId"] = System.Guid.NewGuid().ToString();
                Session["SessionId"] = ViewState["ViewStateId"].ToString();
            }
            else
            {
                if (ViewState["ViewStateId"].ToString() != Session["SessionId"].ToString())
                {
                    IsPageRefresh = true;
                }
                Session["SessionId"] = System.Guid.NewGuid().ToString();
                ViewState["ViewStateId"] = Session["SessionId"].ToString();
            }       
         
        }

protected void btn_Click(object sender, EventArgs e)
        {
            if (!IsPageRefresh)
            {
            }
    }