我开发ios程序，我使用asp网络会话系统。问题是当我关闭程序时，会话正在删除！我该如何处理？
代码部分： protected void Page_Load（object sender，EventArgs e） { Response.Headers.Add（＆＃34; Content-type＆＃34;，＆＃34; text / json＆＃34;）; Response.Headers.Add（＆＃34; Content-type＆＃34;，＆＃34; application / json＆＃34;）; string b = Request.QueryString [＆＃34; routeFunc＆＃34;];
if (b != "user/login")
{
Dictionary<string, string> userData = (Dictionary<string, string>)Session["userData"];
if (userData == null)
{
userData = new Dictionary<string, string>();
userData.Add("false", "0");
echo(JsonConvert.SerializeObject(userData));
return;
}
else
{
Session["userData"] = c_mysql.FindOne("users", "id", userData["id"]);
userData = (Dictionary<string, string>)Session["userData"];
c_user.userData = userData;
c_user.notificationCenter.userData2 = userData;
}