ASP.NET頁面運行時候，頁面將經(jīng)歷一個生命周期，在生命周期中將執(zhí)行一系列的處理步驟。包括初始化、實例化控件、還原和維護狀態(tài)、運行時間處理程序代碼以及進行呈現(xiàn)。熟悉頁面生命周期非常重要，這樣我們才能在生命周期的合適階段編寫代碼。如果我們能在寫代碼的時候想著我們現(xiàn)在是在做生命周期的哪一步那將是非常好的。
幾個代表性的問題
在開始的時候我們先思考幾個問題，看看我們在描述完頁面生命周期的時候，能不能回答上這幾個問題
了解ASP.NET請求管道、應用程序生命周期、整體運行機制童鞋可能知道，ASP.NET應用程序周期中PreRequestHandlerExecute事件與PostRequestHandlerExecute事件之間就是我們的頁面生命周期了，對于aspx頁面就是一系列的打造頁面控件樹，觸發(fā)各種頁面時間，對于一般處理程序ashx就是直接執(zhí)行咱們開發(fā)者寫的ProcessRequest方法了，對于MVC應用程序就是創(chuàng)建控制器工廠，創(chuàng)建控制器對象，調(diào)用Action那一套了。
下面主要講述的就是ASP.NET WebForm中的頁面的生命周期了。
我們用反編譯工具查看Page類的ProcessRequest方法可以看見先調(diào)用了FrameworkInitialize; FrameworkInitialize里面就是打造了頁面控件樹，然后調(diào)用了ProcessRequestMain，就開始了執(zhí)行整個頁面生命周期了（其實就是調(diào)用了一系列的事件方法）（可能部分圖看不見右邊，可在新標簽頁中打開圖片）
1.打造頁面控件樹
FrameworkInitialize內(nèi)部調(diào)用了_buildControlTree（）方法
上圖中左邊是前臺頁面的代碼，右邊是對應 生成的打造控件樹的代碼。中間截取的是生成表單那一部分的代碼。
下面看一張原理圖
瀏覽器的DOM樹是根據(jù)Html標簽生成一個C語言的DOM樹，而ASP.NET服務器端是用C#打造的一個控件樹，也是按照DOM結構打造的。本質(zhì)是一樣。服務器端所有東西都加到頁面對象的控件集合中去了。標簽在服務器端有對應的控件對象的時候就用控件對象，沒有的時候就使用LiteralControl進行封裝。不管是服務器控件還是字符串標簽（沒有runat="server"的標簽）都以控件對象的方式存在前臺頁面類的控件集合里面。好處就是生成前臺頁面的html代碼的時候，只需要遍歷控件集合里面的每一個控件對象的RenderControl方法，每一個控件都會調(diào)用自己的Render方法生成對應的Html字符串。那么所有控件的生成的html字符串就還原成一個頁面的html代碼了。
2.觸發(fā)PerformPreInit事件
在所有初始化之前初始化了這個事件，這個事件主要是初始化了主題，初始化了母版頁
private void PerformPreInit()
{
this.OnPreInit(EventArgs.Empty);
this.InitializeThemes();
this.ApplyMasterPage();
this._preInitWorkComplete = true;
}
3.觸發(fā)InitRecursive事件
4.觸發(fā)LoadAllState()事件
加載頁面狀態(tài)解析ViewState，將頁面表單中的ViewState進行反Base64編碼，反序列化，存在頁面的ViewState屬性中
5.觸發(fā)ProcessPostData(this._requestValueCollection, true)事件
private void ProcessPostData(NameValueCollection postData, bool fBeforeLoad)
{
if (this._changedPostDataConsumers == null)
{
this._changedPostDataConsumers = new ArrayList();
}
if (postData != null)
{
foreach (string str in postData)
{
if ((str != null) !IsSystemPostField(str))
{
Control control = this.FindControl(str);
if (control == null)
{
if (fBeforeLoad)
{
if (this._leftoverPostData == null)
{
this._leftoverPostData = new NameValueCollection();
}
this._leftoverPostData.Add(str, null);
}
}
else
{
IPostBackDataHandler postBackDataHandler = control.PostBackDataHandler;
if (postBackDataHandler == null)
{
if (control.PostBackEventHandler != null)
{
this.RegisterRequiresRaiseEvent(control.PostBackEventHandler);
}
}
else
{
if (postBackDataHandler != null)
{
NameValueCollection postCollection = control.CalculateEffectiveValidateRequest() ? this._requestValueCollection : this._unvalidatedRequestValueCollection;
if (postBackDataHandler.LoadPostData(str, postCollection))
{
this._changedPostDataConsumers.Add(control);
}
}
if (this._controlsRequiringPostBack != null)
{
this._controlsRequiringPostBack.Remove(str);
}
}
}
}
}
}
ArrayList list = null;
if (this._controlsRequiringPostBack != null)
{
foreach (string str2 in this._controlsRequiringPostBack)
{
Control control2 = this.FindControl(str2);
if (control2 != null)
{
IPostBackDataHandler adapterInternal = control2.AdapterInternal as IPostBackDataHandler;
if (adapterInternal == null)
{
adapterInternal = control2 as IPostBackDataHandler;
}
if (adapterInternal == null)
{
object[] args = new object[] { str2 };
throw new HttpException(SR.GetString("Postback_ctrl_not_found", args));
}
NameValueCollection values2 = control2.CalculateEffectiveValidateRequest() ? this._requestValueCollection : this._unvalidatedRequestValueCollection;
if (adapterInternal.LoadPostData(str2, values2))
{
this._changedPostDataConsumers.Add(control2);
}
}
else if (fBeforeLoad)
{
if (list == null)
{
list = new ArrayList();
}
list.Add(str2);
}
}
this._controlsRequiringPostBack = list;
}
}
主要做了兩件事
1）將表單里提交過來的控件數(shù)據(jù)設置給頁面對象的控件樹中對應控件的屬性（給前面打造的控件樹里面控件給值），這樣在服務器端就可以拿到客戶端輸入的值了。
2）將表單里面提交過來的值與ViewState中控件原來的值進行比對，不同則表示要觸發(fā)該控件的Change 事件，則同時將該控件放到一個集合（看源碼其實就是changedPostDataConsumers）中。在后續(xù)執(zhí)行過程中遍歷改集合依次觸發(fā)對應控件的Change事件。
6.觸發(fā)LoadRecursive()事件
大名鼎鼎的Page_Load就是在這里執(zhí)行的。不過是先執(zhí)行頁面本身的Load事件再執(zhí)行頁面控件的Load事件哦,這時候前面給控件賦的值,表單提交過來的數(shù)據(jù),ViewState等等都可以使用了，IsPostBack的原理就是判斷是否有name為__VIEWSTATE的數(shù)據(jù)提交過來
7.再次觸發(fā)ProcessPostData(this._leftoverPostData, false)事件
這個事件我在網(wǎng)上看了很多人說是將第一次遺漏下來的，第一次執(zhí)行ProcessPostData沒有涉及到的控件進行處理，但是并沒有說明哪些遺漏下來了。為什么第一次沒處理了？ 最后Google查到是處理我們開發(fā)者在頁面的Page_Load方法中添加的控件。在Page_Load中我們可以自己創(chuàng)建控件對象加到頁面對應的“C#DOM樹中“，如：在Page_Load中寫
TextBox txt = new TextBox();txt.ID ="myTxtBox";this.form1.Controls.Add(txt);
這就是把開發(fā)者自己創(chuàng)建的控件加在頁面的form1的表單中。當然你也可以加上Change事件了創(chuàng)建控件的時候。執(zhí)行的還是上面那兩件事了。則回發(fā)的時候可以給開發(fā)者在Page_Lod中手動創(chuàng)建的控件還原值。
8.觸發(fā)RaiseChangedEvents事件
循環(huán)遍歷changedPostDataConsumers集合中的所有控件，依次執(zhí)行控件的非點擊回傳事件，比如文本框的改變事件等
9.觸發(fā)RaisePostBackEvent(this._requestValueCollection)事件
執(zhí)行按鈕點擊回傳事件或者驗證事件，如果有多個按鈕，根據(jù)回發(fā)過來的按鈕的 name來判斷觸發(fā)哪個按鈕的事件，或者觸發(fā)該控件的驗證事件
10.觸發(fā)PerformPreRenderComplete事件
循環(huán)遍歷控件樹中所有的控件，根據(jù)每個控件生成對應的Html代碼，把服務器控件渲染成普通的html控件。
11.觸發(fā)事件SaveAllState事件
將服務器端ViewState集合中的內(nèi)容（開發(fā)者自己加的數(shù)據(jù)或控件狀態(tài)信息等）序列化然后Base64編碼然后設置到客戶端隱藏域__ViewState中
12.RenderControl(this.CreateHtmlTextWriter(this.Response.Output))
把要發(fā)送到客戶端瀏覽器的內(nèi)容設置到Response.Output，應用程序?qū)⑺l(fā)送 到客戶端瀏覽器。[/code]
看到這里不知道大家是否已經(jīng)可以清晰地回答開篇提到的幾個問題了，其實就是這些事件執(zhí)行的先后順序，頁面生命周期了。”前人植樹，后人乘涼了"
最后附上生命周期ProcessRequest源碼
private void ProcessRequestMain(bool includeStagesBeforeAsyncPoint, bool includeStagesAfterAsyncPoint)
{
try
{
HttpContext context = this.Context;
string str = null;
if (includeStagesBeforeAsyncPoint)
{
if (this.IsInAspCompatMode)
{
AspCompatApplicationStep.OnPageStartSessionObjects();
}
if (this.PageAdapter != null)
{
this._requestValueCollection = this.PageAdapter.DeterminePostBackMode();
if (this._requestValueCollection != null)
{
this._unvalidatedRequestValueCollection = this.PageAdapter.DeterminePostBackModeUnvalidated();
}
}
else
{
this._requestValueCollection = this.DeterminePostBackMode();
if (this._requestValueCollection != null)
{
this._unvalidatedRequestValueCollection = this.DeterminePostBackModeUnvalidated();
}
}
string callbackControlID = string.Empty;
if (this.DetermineIsExportingWebPart())
{
if (!RuntimeConfig.GetAppConfig().WebParts.EnableExport)
{
throw new InvalidOperationException(SR.GetString("WebPartExportHandler_DisabledExportHandler"));
}
str = this.Request.QueryString["webPart"];
if (string.IsNullOrEmpty(str))
{
throw new InvalidOperationException(SR.GetString("WebPartExportHandler_InvalidArgument"));
}
if (string.Equals(this.Request.QueryString["scope"], "shared", StringComparison.OrdinalIgnoreCase))
{
this._pageFlags.Set(4);
}
string str3 = this.Request.QueryString["query"];
if (str3 == null)
{
str3 = string.Empty;
}
this.Request.QueryStringText = str3;
context.Trace.IsEnabled = false;
}
if (this._requestValueCollection != null)
{
if (this._requestValueCollection["__VIEWSTATEENCRYPTED"] != null)
{
this.ContainsEncryptedViewState = true;
}
callbackControlID = this._requestValueCollection["__CALLBACKID"];
if ((callbackControlID != null) (this._request.HttpVerb == HttpVerb.POST))
{
this._isCallback = true;
}
else if (!this.IsCrossPagePostBack)
{
VirtualPath path = null;
if (this._requestValueCollection["__PREVIOUSPAGE"] != null)
{
try
{
path = VirtualPath.CreateNonRelativeAllowNull(DecryptString(this._requestValueCollection["__PREVIOUSPAGE"], Purpose.WebForms_Page_PreviousPageID));
}
catch
{
this._pageFlags[8] = true;
}
if ((path != null) (path != this.Request.CurrentExecutionFilePathObject))
{
this._pageFlags[8] = true;
this._previousPagePath = path;
}
}
}
}
if (this.MaintainScrollPositionOnPostBack)
{
this.LoadScrollPosition();
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreInit");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_INIT_ENTER, this._context.WorkerRequest);
}
this.PerformPreInit();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_INIT_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreInit");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin Init");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_INIT_ENTER, this._context.WorkerRequest);
}
this.InitRecursive(null);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_INIT_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Init");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin InitComplete");
}
this.OnInitComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End InitComplete");
}
if (this.IsPostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin LoadState");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_VIEWSTATE_ENTER, this._context.WorkerRequest);
}
this.LoadAllState();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_VIEWSTATE_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End LoadState");
this.Trace.Write("aspx.page", "Begin ProcessPostData");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_POSTDATA_ENTER, this._context.WorkerRequest);
}
this.ProcessPostData(this._requestValueCollection, true);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_POSTDATA_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End ProcessPostData");
}
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreLoad");
}
this.OnPreLoad(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreLoad");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin Load");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_ENTER, this._context.WorkerRequest);
}
this.LoadRecursive();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Load");
}
if (this.IsPostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin ProcessPostData Second Try");
}
this.ProcessPostData(this._leftoverPostData, false);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End ProcessPostData Second Try");
this.Trace.Write("aspx.page", "Begin Raise ChangedEvents");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_POST_DATA_CHANGED_ENTER, this._context.WorkerRequest);
}
this.RaiseChangedEvents();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_POST_DATA_CHANGED_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Raise ChangedEvents");
this.Trace.Write("aspx.page", "Begin Raise PostBackEvent");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RAISE_POSTBACK_ENTER, this._context.WorkerRequest);
}
this.RaisePostBackEvent(this._requestValueCollection);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RAISE_POSTBACK_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Raise PostBackEvent");
}
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin LoadComplete");
}
this.OnLoadComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End LoadComplete");
}
if (this.IsPostBack this.IsCallback)
{
this.PrepareCallback(callbackControlID);
}
else if (!this.IsCrossPagePostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreRender");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_RENDER_ENTER, this._context.WorkerRequest);
}
this.PreRenderRecursiveInternal();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_RENDER_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreRender");
}
}
}
if ((this._legacyAsyncInfo == null) || this._legacyAsyncInfo.CallerIsBlocking)
{
this.ExecuteRegisteredAsyncTasks();
}
this.ValidateRawUrlIfRequired();
if (includeStagesAfterAsyncPoint)
{
if (this.IsCallback)
{
this.RenderCallback();
}
else if (!this.IsCrossPagePostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreRenderComplete");
}
this.PerformPreRenderComplete();
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreRenderComplete");
}
if (context.TraceIsEnabled)
{
this.BuildPageProfileTree(this.EnableViewState);
this.Trace.Write("aspx.page", "Begin SaveState");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_SAVE_VIEWSTATE_ENTER, this._context.WorkerRequest);
}
this.SaveAllState();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_SAVE_VIEWSTATE_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End SaveState");
this.Trace.Write("aspx.page", "Begin SaveStateComplete");
}
this.OnSaveStateComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End SaveStateComplete");
this.Trace.Write("aspx.page", "Begin Render");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RENDER_ENTER, this._context.WorkerRequest);
}
if (str != null)
{
this.ExportWebPart(str);
}
else
{
this.RenderControl(this.CreateHtmlTextWriter(this.Response.Output));
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RENDER_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Render");
}
this.CheckRemainingAsyncTasks(false);
}
}
}
catch (ThreadAbortException exception1)
{
HttpApplication.CancelModuleException exceptionState = exception1.ExceptionState as HttpApplication.CancelModuleException;
if ((((includeStagesBeforeAsyncPoint includeStagesAfterAsyncPoint) (this._context.Handler == this)) ((this._context.ApplicationInstance != null) (exceptionState != null))) !exceptionState.Timeout)
{
this._context.ApplicationInstance.CompleteRequest();
ThreadResetAbortWithAssert();
}
else
{
this.CheckRemainingAsyncTasks(true);
throw;
}
}
catch (ConfigurationException)
{
throw;
}
catch (Exception exception2)
{
PerfCounters.IncrementCounter(AppPerfCounter.ERRORS_DURING_REQUEST);
PerfCounters.IncrementCounter(AppPerfCounter.ERRORS_TOTAL);
if (!this.HandleError(exception2))
{
throw;
}
}
}
private void ProcessRequestMain(bool includeStagesBeforeAsyncPoint, bool includeStagesAfterAsyncPoint)
{
try
{
HttpContext context = this.Context;
string str = null;
if (includeStagesBeforeAsyncPoint)
{
if (this.IsInAspCompatMode)
{
AspCompatApplicationStep.OnPageStartSessionObjects();
}
if (this.PageAdapter != null)
{
this._requestValueCollection = this.PageAdapter.DeterminePostBackMode();
if (this._requestValueCollection != null)
{
this._unvalidatedRequestValueCollection = this.PageAdapter.DeterminePostBackModeUnvalidated();
}
}
else
{
this._requestValueCollection = this.DeterminePostBackMode();
if (this._requestValueCollection != null)
{
this._unvalidatedRequestValueCollection = this.DeterminePostBackModeUnvalidated();
}
}
string callbackControlID = string.Empty;
if (this.DetermineIsExportingWebPart())
{
if (!RuntimeConfig.GetAppConfig().WebParts.EnableExport)
{
throw new InvalidOperationException(SR.GetString("WebPartExportHandler_DisabledExportHandler"));
}
str = this.Request.QueryString["webPart"];
if (string.IsNullOrEmpty(str))
{
throw new InvalidOperationException(SR.GetString("WebPartExportHandler_InvalidArgument"));
}
if (string.Equals(this.Request.QueryString["scope"], "shared", StringComparison.OrdinalIgnoreCase))
{
this._pageFlags.Set(4);
}
string str3 = this.Request.QueryString["query"];
if (str3 == null)
{
str3 = string.Empty;
}
this.Request.QueryStringText = str3;
context.Trace.IsEnabled = false;
}
if (this._requestValueCollection != null)
{
if (this._requestValueCollection["__VIEWSTATEENCRYPTED"] != null)
{
this.ContainsEncryptedViewState = true;
}
callbackControlID = this._requestValueCollection["__CALLBACKID"];
if ((callbackControlID != null) (this._request.HttpVerb == HttpVerb.POST))
{
this._isCallback = true;
}
else if (!this.IsCrossPagePostBack)
{
VirtualPath path = null;
if (this._requestValueCollection["__PREVIOUSPAGE"] != null)
{
try
{
path = VirtualPath.CreateNonRelativeAllowNull(DecryptString(this._requestValueCollection["__PREVIOUSPAGE"], Purpose.WebForms_Page_PreviousPageID));
}
catch
{
this._pageFlags[8] = true;
}
if ((path != null) (path != this.Request.CurrentExecutionFilePathObject))
{
this._pageFlags[8] = true;
this._previousPagePath = path;
}
}
}
}
if (this.MaintainScrollPositionOnPostBack)
{
this.LoadScrollPosition();
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreInit");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_INIT_ENTER, this._context.WorkerRequest);
}
this.PerformPreInit();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_INIT_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreInit");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin Init");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_INIT_ENTER, this._context.WorkerRequest);
}
this.InitRecursive(null);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_INIT_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Init");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin InitComplete");
}
this.OnInitComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End InitComplete");
}
if (this.IsPostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin LoadState");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_VIEWSTATE_ENTER, this._context.WorkerRequest);
}
this.LoadAllState();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_VIEWSTATE_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End LoadState");
this.Trace.Write("aspx.page", "Begin ProcessPostData");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_POSTDATA_ENTER, this._context.WorkerRequest);
}
this.ProcessPostData(this._requestValueCollection, true);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_POSTDATA_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End ProcessPostData");
}
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreLoad");
}
this.OnPreLoad(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreLoad");
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin Load");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_ENTER, this._context.WorkerRequest);
}
this.LoadRecursive();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_LOAD_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Load");
}
if (this.IsPostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin ProcessPostData Second Try");
}
this.ProcessPostData(this._leftoverPostData, false);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End ProcessPostData Second Try");
this.Trace.Write("aspx.page", "Begin Raise ChangedEvents");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_POST_DATA_CHANGED_ENTER, this._context.WorkerRequest);
}
this.RaiseChangedEvents();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_POST_DATA_CHANGED_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Raise ChangedEvents");
this.Trace.Write("aspx.page", "Begin Raise PostBackEvent");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RAISE_POSTBACK_ENTER, this._context.WorkerRequest);
}
this.RaisePostBackEvent(this._requestValueCollection);
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RAISE_POSTBACK_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Raise PostBackEvent");
}
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin LoadComplete");
}
this.OnLoadComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End LoadComplete");
}
if (this.IsPostBack this.IsCallback)
{
this.PrepareCallback(callbackControlID);
}
else if (!this.IsCrossPagePostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreRender");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_RENDER_ENTER, this._context.WorkerRequest);
}
this.PreRenderRecursiveInternal();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_PRE_RENDER_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreRender");
}
}
}
if ((this._legacyAsyncInfo == null) || this._legacyAsyncInfo.CallerIsBlocking)
{
this.ExecuteRegisteredAsyncTasks();
}
this.ValidateRawUrlIfRequired();
if (includeStagesAfterAsyncPoint)
{
if (this.IsCallback)
{
this.RenderCallback();
}
else if (!this.IsCrossPagePostBack)
{
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "Begin PreRenderComplete");
}
this.PerformPreRenderComplete();
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End PreRenderComplete");
}
if (context.TraceIsEnabled)
{
this.BuildPageProfileTree(this.EnableViewState);
this.Trace.Write("aspx.page", "Begin SaveState");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_SAVE_VIEWSTATE_ENTER, this._context.WorkerRequest);
}
this.SaveAllState();
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_SAVE_VIEWSTATE_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End SaveState");
this.Trace.Write("aspx.page", "Begin SaveStateComplete");
}
this.OnSaveStateComplete(EventArgs.Empty);
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End SaveStateComplete");
this.Trace.Write("aspx.page", "Begin Render");
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RENDER_ENTER, this._context.WorkerRequest);
}
if (str != null)
{
this.ExportWebPart(str);
}
else
{
this.RenderControl(this.CreateHtmlTextWriter(this.Response.Output));
}
if (EtwTrace.IsTraceEnabled(5, 4))
{
EtwTrace.Trace(EtwTraceType.ETW_TYPE_PAGE_RENDER_LEAVE, this._context.WorkerRequest);
}
if (context.TraceIsEnabled)
{
this.Trace.Write("aspx.page", "End Render");
}
this.CheckRemainingAsyncTasks(false);
}
}
}
catch (ThreadAbortException exception1)
{
HttpApplication.CancelModuleException exceptionState = exception1.ExceptionState as HttpApplication.CancelModuleException;
if ((((includeStagesBeforeAsyncPoint includeStagesAfterAsyncPoint) (this._context.Handler == this)) ((this._context.ApplicationInstance != null) (exceptionState != null))) !exceptionState.Timeout)
{
this._context.ApplicationInstance.CompleteRequest();
ThreadResetAbortWithAssert();
}
else
{
this.CheckRemainingAsyncTasks(true);
throw;
}
}
catch (ConfigurationException)
{
throw;
}
catch (Exception exception2)
{
PerfCounters.IncrementCounter(AppPerfCounter.ERRORS_DURING_REQUEST);
PerfCounters.IncrementCounter(AppPerfCounter.ERRORS_TOTAL);
if (!this.HandleError(exception2))
{
throw;
}
}
}
以上就是關于ASP.NET頁面生命周期的詳細內(nèi)容介紹，希望對大家的學習有所幫助。
