在ASPX WebMethod的AJAX调用之间ASP.Net会话更改

Question

I have a single page application that starts off with default.aspx creating the basic HTML layout and then I use AJAX calls to get data from static WebMethods in other aspx pages. I also have a KeepAlive.aspx that reloads every once in a while to keep the session alive.

The login form that appears initially calls the login webmethod which uses an external web service to login and store user information in the session. I use HttpContext.Current.Session to get and set values in the session.

The very next web method that I call is to getuserpreferences from the external web service using identity information obtained at login time.

This is all working fine and dandy on various IIS servers. Recently we deployed this on a new server and it is not working there.

It does successfully login and saves the user values in session, but when the next ajax call to getuserpreferences happens, the getuserpreferences web method tries to get the session values... and it is NOT there any more!

I put in a bunch of logging and saw that session Id is changing! The login session id is different from the session id that I see from get userpreferences, even though both use HttpContext.Current.Session.

On the servers that it does work, sometimes (randomly?) it does behave in a similar way: it loses session values and throws me back to login.

Please provide help/tips to trace this issue and ensure the same session continues across ajax calls. This is not an MVC or WebAPI project; it is a simple aspx application.

UPDATE (Jan 8) : I found the difference in behavior between the instances where this works and where it doesn't: ASP.Net_SessionId cookie value is being set where it works, but in this case it is not being set and is therefore not maintaining session state. Now I need to figure out why it is not setting.

Update 2 (Jan 8) : When we installed a certificate on the server and implemented https, the session Id cookie started appearing. So although the issue is no longer urgent, I do want to find out why HTTP did not work.

Code:

WebServiceHelper.js

    WebServiceHelper.prototype.invokeServiceMethod = function(serviceName, methodName, params, returntype) {
    var self = this;
    var obj = {};
    var def = $.Deferred();
    var url = serviceName + "/" + methodName;
    $.support.cors = true;
    $.ajax({
        url: url,
        data: ko.toJSON(params),
        type: "POST",
        dataType: "json",
        contentType: "application/json; charset=utf-8",
        success: function(mydata) {

            if (mydata && mydata.d) {

                    def.resolve(mydata.d);
                }                

        },
        error: function(msg) {

                def.reject(msg);
        }
    });

    return def.promise();
};

Data Provider.js:

   DataProvider.prototype.loginUser = function(email, password, token) {
    var self = this;
    var def = $.Deferred();

    var webServiceHelper = new WebServiceHelper();

    webServiceHelper.invokeServiceMethod("Login.aspx", "LoginUser", { email: email, password: password, token: token }, "json").done(function (retObj) {
        self.userObj = retObj.userinfo;
        self.loginTime = new Date();
        self.loadInitialData();
        def.resolve();
    }).fail(
        function(retObj1) {
                def.reject(retObj1);
        });

    return def.promise();
};

Preference Manager.js

    PreferenceManager.prototype.invokeGetPreferences = function (prefKey) {
    var self = this;

    var def = $.Deferred();

    var webServiceHelper = new WebServiceHelper();

    webServiceHelper.invokeServiceMethod("WebMethods.aspx", "GetPreferences", { key: prefKey }, "json").done(function (retObj) {
        def.resolve(retObj);
    }).fail(
        function (retObj1) {
                def.reject(retObj1);
        });

    return def.promise();

};

Login.aspx.cs:

        [WebMethod(EnableSession=true)]
    public static string LoginUser(string email, string password, string token)
    {
        if (Authenticate(email, password, token))
        {
            HttpContext.Current.Session["vanalyticsLastLoginDateTime"] = DateTime.Now;

            var userjson =  GetUserJson();

            Logger.Debug("Login - Session Id {0} - Returning user json {1}", HttpContext.Current.Session.SessionID, userjson);

            return userjson;
        }

        return "Error: " + _validationError;
    }

        private static bool Authenticate(string stremail, string strpassword, string token)
    {
        var vplug = new vPlugin();

        HttpContext.Current.Session.Remove("vUserInfo");

        vplug.Authenticate(HttpContext.Current, appsurl, stremail, strpassword, token);

        _validationError = vplug.LastException != null ? vplug.LastException.Message : null;

        return (HttpContext.Current.Session["vUserInfo"] != null);
    }

vPlugin code: (eventually calls setuser)

 private void SetUser(HttpContext obj, userInfo user)
    {
        HttpSessionState session = obj.Session;

        session["vUserInfo"] = user;
        ....
        session["vDataToken"] = setting.ContainsKey("token") ? setting["token"] : "0-0";
    }

WebMethods.aspx:

    [WebMethod(EnableSession=true)]
    public static string GetPreferences(string key)
    {
        var myadr = new ADR.VrtDataService { Timeout = 20000 };

        var token = GetTokenFromSession();

        try
        {
            var result = myadr.getPreference(token, key);

            myadr.Dispose();

            return result;
        }
        catch (Exception ex)
        {
            return "Error: " + ex.Message;
        }
    }

       public static string GetTokenFromSession()
    {
        var token = "";

        var val2 = HttpContext.Current.Session["vDataToken"];

        if (val2 != null)
        {
            token = (string) val2;
        }
        else
        {
            Logger.Error("Token is blank, session id is " + HttpContext.Current.Session.SessionID);
        }

        return token;
    }

I am getting 'Token is blank' and the session id is different from the Id logged by the login method earlier.

Also, please note that the entire code is in JavaScript and aspx only serves as RESTful API with session.

Answer 1

很简单，只需使用HttpContext.Current.Session["user_id"] = ""