SessionStateUtility.AddHttpSessionStateToContext 方法

定義

命名空間:

System.Web.SessionState

組件:

System.Web.dll

將工作階段資料套用至目前要求的內容。

public:
 static void AddHttpSessionStateToContext(System::Web::HttpContext ^ context, System::Web::SessionState::IHttpSessionState ^ container);

public static void AddHttpSessionStateToContext (System.Web.HttpContext context, System.Web.SessionState.IHttpSessionState container);

static member AddHttpSessionStateToContext : System.Web.HttpContext * System.Web.SessionState.IHttpSessionState -> unit

Public Shared Sub AddHttpSessionStateToContext (context As HttpContext, container As IHttpSessionState)

參數

context

HttpContext

要加入 HttpContext 物件的 HttpSessionState 物件。

container

IHttpSessionState

要加入至指定 HTTP 內容的 IHttpSessionState 實作執行個體。

例外狀況

HttpException

目前工作階段的 HttpSessionState 物件已加入至指定的 context。

範例

下列程式碼範例顯示自訂會話狀態模組中事件的處理常式 AcquireRequestState 。 自訂模組會擷取現有的會話資訊，或建立新的會話資訊，並使用 AddHttpSessionStateToContext 方法將它新增至 HttpContext 目前要求的 。 此程式碼範例是提供給 類別之較大範例的 SessionStateUtility 一部分。

//
// Event handler for HttpApplication.AcquireRequestState
//

private void OnAcquireRequestState(object source, EventArgs args)
{
    HttpApplication app = (HttpApplication)source;
    HttpContext context = app.Context;
    bool isNew = false;
    string sessionID;
    SessionItem sessionData = null;
    bool supportSessionIDReissue = true;

    pSessionIDManager.InitializeRequest(context, false, out supportSessionIDReissue);
    sessionID = pSessionIDManager.GetSessionID(context);

    if (sessionID != null)
    {
        try
        {
            pHashtableLock.AcquireReaderLock(Int32.MaxValue);
            sessionData = (SessionItem)pSessionItems[sessionID];

            if (sessionData != null)
               sessionData.Expires = DateTime.Now.AddMinutes(pTimeout);
        }
        finally
        {
            pHashtableLock.ReleaseReaderLock();
        }
    }
    else
    {
        bool redirected, cookieAdded;

        sessionID = pSessionIDManager.CreateSessionID(context);
        pSessionIDManager.SaveSessionID(context, sessionID, out redirected, out cookieAdded);

        if (redirected)
            return;
    }

    if (sessionData == null)
    {
        // Identify the session as a new session state instance. Create a new SessionItem
        // and add it to the local Hashtable.

        isNew = true;

        sessionData = new SessionItem();

        sessionData.Items = new SessionStateItemCollection();
        sessionData.StaticObjects = SessionStateUtility.GetSessionStaticObjects(context);
        sessionData.Expires = DateTime.Now.AddMinutes(pTimeout);

        try
        {
            pHashtableLock.AcquireWriterLock(Int32.MaxValue);
            pSessionItems[sessionID] = sessionData;
        }
        finally
        {
            pHashtableLock.ReleaseWriterLock();
        }
    }

    // Add the session data to the current HttpContext.
    SessionStateUtility.AddHttpSessionStateToContext(context,
                     new HttpSessionStateContainer(sessionID,
                                                  sessionData.Items,
                                                  sessionData.StaticObjects,
                                                  pTimeout,
                                                  isNew,
                                                  pCookieMode,
                                                  SessionStateMode.Custom,
                                                  false));

    // Execute the Session_OnStart event for a new session.
    if (isNew && Start != null)
    {
        Start(this, EventArgs.Empty);
    }
}

//
// Event for Session_OnStart event in the Global.asax file.
//

public event EventHandler Start;

    '
    ' Event handler for HttpApplication.AcquireRequestState
    '
    Private Sub OnAcquireRequestState(ByVal [source] As Object, ByVal args As EventArgs)
        Dim app As HttpApplication = CType([source], HttpApplication)
        Dim context As HttpContext = app.Context
        Dim isNew As Boolean = False
        Dim sessionID As String
        Dim sessionData As SessionItem = Nothing
        Dim supportSessionIDReissue As Boolean = True

        pSessionIDManager.InitializeRequest(context, False, supportSessionIDReissue)
        sessionID = pSessionIDManager.GetSessionID(context)


        If Not (sessionID Is Nothing) Then
            Try
                pHashtableLock.AcquireReaderLock(Int32.MaxValue)
                sessionData = CType(pSessionItems(sessionID), SessionItem)

                If Not (sessionData Is Nothing) Then
                    sessionData.Expires = DateTime.Now.AddMinutes(pTimeout)
                End If
            Finally
                pHashtableLock.ReleaseReaderLock()
            End Try
        Else
            Dim redirected, cookieAdded As Boolean

            sessionID = pSessionIDManager.CreateSessionID(context)
            pSessionIDManager.SaveSessionID(context, sessionID, redirected, cookieAdded)

            If redirected Then Return
        End If
        If sessionData Is Nothing Then
            ' Identify the session as a new session state instance. Create a new SessionItem
            ' and add it to the local Hashtable.
            isNew = True

            sessionData = New SessionItem()

            sessionData.Items = New SessionStateItemCollection()
            sessionData.StaticObjects = SessionStateUtility.GetSessionStaticObjects(context)
            sessionData.Expires = DateTime.Now.AddMinutes(pTimeout)

            Try
                pHashtableLock.AcquireWriterLock(Int32.MaxValue)
                pSessionItems(sessionID) = sessionData
            Finally
                pHashtableLock.ReleaseWriterLock()
            End Try
        End If

        ' Add the session data to the current HttpContext.
        SessionStateUtility.AddHttpSessionStateToContext(context, _
                         New HttpSessionStateContainer(sessionID, _
                                                      sessionData.Items, _
                                                      sessionData.StaticObjects, _
                                                      pTimeout, _
                                                      isNew, _
                                                      pCookieMode, _
                                                      SessionStateMode.Custom, _
                                                      False))

        ' Execute the Session_OnStart event for a new session.
        If isNew Then RaiseEvent Start(Me, EventArgs.Empty)
    End Sub


    '
    ' Event for Session_OnStart event in the Global.asax file.
    '
Public Event Start As EventHandler

備註

會話 AddHttpSessionStateToContext 狀態模組會使用 方法，將會話資料套用至目前的要求。 這發生在要求開始時的事件期間 AcquireRequestState 。 目前要求的會話資料會針對現有會話擷取，或針對新會話建立。 會話資料接著會封裝在實作實例中 IHttpSessionState ，此實例會連同目前的 HttpContext 一起傳遞至 AddHttpSessionStateToContext 方法。 接著會透過 Session 目前內容的 屬性，將提供的會話資料提供給應用程式程式碼使用。