【转】后退显示网页已过期

  Response.Buffer = true;  
  Response.ExpiresAbsolute = DateTime.Now.AddDays(-1);  
  Response.Expires = 0 ;  
  Response.Cache.SetExpires( DateTime.Now.AddDays(-1));  
  Response.Cache.SetNoStore();  
  Response.Expires = 0;  
  Response.AppendHeader("pragma","no-cache"); 
  Response.AppendHeader("cache-control","private");
  Response.Cache.SetExpires(DateTime.Now.AddSeconds(-60));
  Response.Cache.SetCacheability(HttpCacheability.NoCache);
  Response.Cache.SetValidUntilExpires(false);