c# - Global.asax 中的 HttpApplication.Context null

Question

引用此answer regarding regenerating new SessionID

我在 Global.asax.cs 中创建了此代码:

        protected void Application_Start(object sender, EventArgs e)
        {
            Bootstrapper.Initialized += new EventHandler<ExecutedEventArgs>(Bootstrapper_Initialized);
        }

        void Bootstrapper_Initialized(object sender, Telerik.Sitefinity.Data.ExecutedEventArgs e)
        {
            if (e.CommandName == "Bootstrapped")
            {
                EventHub.Subscribe<ILoginCompletedEvent>(LoginCompletedEventVerification);
            }
        }


        private void LoginCompletedEventVerification(ILoginCompletedEvent evt)
        {
            if (evt.LoginResult == UserLoggingReason.Success)
            {
                var manager = new SessionIDManager();
                var oldId = manager.GetSessionID(Context);
                var newId = manager.CreateSessionID(Context);
                bool isAdd = false, isRedir = false;
                manager.SaveSessionID(Context, newId, out isRedir, out isAdd);
                var ctx = HttpContext.Current.ApplicationInstance;
                var mods = ctx.Modules;
                var ssm = (SessionStateModule)mods.Get("Session");
                var fields = ssm.GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Instance);
                SessionStateStoreData rqItem = null;
                SessionStateStoreProviderBase store = null;
                FieldInfo rqIdField = null, rqLockIdField = null, rqStateNotFoundField = null;
                foreach (var field in fields)
                {
                    if (field.Name.Equals("_store")) store = (SessionStateStoreProviderBase)field.GetValue(ssm);
                    if (field.Name.Equals("_rqId")) rqIdField = field;
                    if (field.Name.Equals("_rqLockId")) rqLockIdField = field;
                    if (field.Name.Equals("_rqSessionStateNotFound")) rqStateNotFoundField = field;
                    if ((field.Name.Equals("_rqItem")))
                    {
                        rqItem = (SessionStateStoreData)field.GetValue(ssm);
                    }
                }
                var lockId = rqLockIdField.GetValue(ssm);
                if ((lockId != null) && (oldId != null))
                {
                    store.ReleaseItemExclusive(Context, oldId, lockId);
                    store.RemoveItem(Context, oldId, lockId, rqItem);
                }
                rqStateNotFoundField.SetValue(ssm, true);
                rqIdField.SetValue(ssm, newId);
            }
        }

请记住，我正在 Sitefinity Web 应用程序中进行开发。 每次我的应用程序在成功登录期间点击 LoginCompletedEventVerification 时，Context 都会显示为 null。现在，我最初想将此代码段添加到 Sitefinity LoginWidget 中，但实现这一目标完全是另一回事。

我没有将其包含在代码示例中，但我确实触发了 Session_Start 来创建我的应用程序的“购物车”。我只是想在身份验证后为购物车创建一个新的 SessionID。

在此事件期间我无法获取 Context 的值是否有原因？

提前致谢。我感谢任何建议或批评!

编辑: Sitefinity knowledge base article where I got my Bootstrapper_Initialized code

Answer 1

I did not include it in the code sample, but I do have Session_Start firing to create my application's "shopping cart." I am just trying to create a new SessionID for the cart after authentication.

不哦。忘记在 Application_Start 事件中访问 HttpContext。

或者，您可以在 Application_BeginRequest 中执行此操作:

private static object syncRoot = new object();
private static bool initialized = false;
public void Application_BeginRequest(object sender, EventArgs e)
{
    if (!initialized)
    {
        lock (syncRoot)
        {
            if (!initialized)
            {
                // Do your stuff here with HttpContext

                initialized = true;
            }
        }
    }
}

您应该注意的另一件事是，HttpContext 在您可能已生成且 HTTP 请求已完成执行的任何后台线程中不可用。因此，在尝试访问此 HttpContext 时应格外小心。