ASP.NET防后退

如有页面Admin，则在其cs文件中写如下代码：
protected void Page_Load(object sender, EventArgs e)
{
Response.AddHeader("Cache-Control", "no-cache");
Response.Expires = -1;
Response.Cache.SetNoStore();
Response.AddHeader("Pragma", "no-cache");
Response.AddHeader("Last-Modified", DateTime.Now.ToString() + " GMT");
Response.Cache.SetCacheability(HttpCacheability.NoCache);
if (Session["AdminNumber"] == null)
{
Response.Redirect("~/Login.aspx");
}
}
在Login页的cs文件中写如下代码：
protected void Page_Load(object sender, EventArgs e)
{
Response.AddHeader("Cache-Control", "no-cache");
Response.Expires = -1;
Response.Cache.SetNoStore();
Response.AddHeader("Pragma", "no-cache");
Response.AddHeader("Last-Modified", DateTime.Now.ToString() + " GMT");
Response.Cache.SetCacheability(HttpCacheability.NoCache);
if (!IsPostBack)
{
Session.Clear();
}
}

如此便可轻松拒绝页面的回退！