在Asp.Net中浏览器刷新上的页面重定向

Question

I am developing a Web app for conducting a Online examination. I want to stop the contestants from refreshing the page in the browser. If they do I want to navigate them to a page which says they are disqualified. How can I implement this?

Answer 1

The following code snippet detects 'Refresh' in page_load function

    bool IsPageRefresh = false;

    protected void Page_Load(object sender, EventArgs e)
    {
        //this section of code checks if the page postback is due to genuine submit by user or by pressing "refresh"

        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();
        }
    }

You can then use the 'IsPageRefresh' boolean flag in the code-behind to determine if it's a postback due to genuine User submit action or by browser 'Refresh'.