SessionStateUtility.GetSessionStaticObjects(HttpContext) 方法

定義

命名空間:

System.Web.SessionState

組件:

System.Web.dll

取得對指定內容之靜態物件集合的參考。

public:
 static System::Web::HttpStaticObjectsCollection ^ GetSessionStaticObjects(System::Web::HttpContext ^ context);

public static System.Web.HttpStaticObjectsCollection GetSessionStaticObjects (System.Web.HttpContext context);

static member GetSessionStaticObjects : System.Web.HttpContext -> System.Web.HttpStaticObjectsCollection

Public Shared Function GetSessionStaticObjects (context As HttpContext) As HttpStaticObjectsCollection

參數

context

HttpContext

供取得靜態物件集合的 HttpContext。

傳回

HttpStaticObjectsCollection

HttpStaticObjectsCollection 集合，使用指定 StaticObjects 的 HttpContext 屬性值填入。

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 。 模組會擷取現有的會話資訊或建立新的會話資訊，包括 HttpStaticObjectsCollection 從 方法傳回的 GetSessionStaticObjects 集合，並將它新增至 HttpContext 目前要求的 。 此程式碼範例是針對 類別提供的較大範例的 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

方法 GetSessionStaticObjects 可用來擷取 ASP.NET 應用程式之 Global.asax 檔案中定義的靜態物件集合。 會話狀態模組實作會將傳 HttpStaticObjectsCollection 回的集合 IHttpSessionState 提供給使用 AddHttpSessionStateToContext 方法新增至目前內容的實作實例。

SessionStateStoreProviderBase也可以在建立 SessionStateStoreData 物件時使用 GetSessionStaticObjects 方法。