MVC系列（3） HttpRuntime詳解分析（下）

文章內容

話說，經過各種各樣復雜的我們不知道的內部處理，非托管代碼正式開始調用ISPAIRuntime的 ProcessRequest方法了（ISPAIRuntime繼承了IISPAIRuntime接口，該接口可以和COM進行交互，並且暴露了 ProcessRequest接口方法）。至於為什麼要調用這個方法，大叔也不太清楚，找不到微軟相關的資料哦。但大叔確定該方法就是我們進入 HttpRuntime的正式大門，接著看吧。

public int ProcessRequest(IntPtr ecb, int iWRType) {  
      
    IntPtr pHttpCompletion = IntPtr.Zero;  
      
    if (iWRType == WORKER_REQUEST_TYPE_IN_PROC_VERSION_2) {  
      
        pHttpCompletion = ecb;  
      
        ecb = UnsafeNativeMethods.GetEcb(pHttpCompletion);  
      
    }  
      
    ISAPIWorkerRequest wr = null;  
      
    try {  
      
        bool useOOP = (iWRType == WORKER_REQUEST_TYPE_OOP);  
      
        wr = ISAPIWorkerRequest.CreateWorkerRequest(ecb, useOOP);  
      
        wr.Initialize();  
      
       
      
        // check if app path matches (need to restart app domain?)  
      
        String wrPath = wr.GetAppPathTranslated();  
      
        String adPath = HttpRuntime.AppDomainAppPathInternal;  
      
       
      
        if (adPath == null ||  
      
            StringUtil.EqualsIgnoreCase(wrPath, adPath)) {   
      
            HttpRuntime.ProcessRequestNoDemand(wr);  
      
            return 0;  
      
        }  
      
        else {  
      
            // need to restart app domain  
      
            HttpRuntime.ShutdownAppDomain(ApplicationShutdownReason.PhysicalApplicationPathChanged,  
      
                                            SR.GetString(SR.Hosting_Phys_Path_Changed,  
      
                                                                            adPath,  
      
                                                                            wrPath));  
      
            return 1;  
      
        }  
      
    }  
      
    catch(Exception e) {  
      
        try {  
      
            WebBaseEvent.RaiseRuntimeError(e, this);  
      
        } catch {}  
      
       
      
        // Have we called HSE_REQ_DONE_WITH_SESSION?  If so, don't re-throw.  
      
        if (wr != null && wr.Ecb == IntPtr.Zero) {  
      
            if (pHttpCompletion != IntPtr.Zero) {  
      
                UnsafeNativeMethods.SetDoneWithSessionCalled(pHttpCompletion);  
      
            }  
      
            // if this is a thread abort exception, cancel the abort  
      
            if (e is ThreadAbortException) {  
      
                Thread.ResetAbort();  
      
            }  
      
            // IMPORTANT: if this thread is being aborted because of an AppDomain.Unload,  
      
            // the CLR will still throw an AppDomainUnloadedException. The native caller  
      
            // must special case COR_E_APPDOMAINUNLOADED(0x80131014) and not  
      
            // call HSE_REQ_DONE_WITH_SESSION more than once.  
      
            return 0;  
      
        }   
      
        // re-throw if we have not called HSE_REQ_DONE_WITH_SESSION  
      
        throw;  
    }  
}