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ActiveX多线程调用javascript回调例程的麻烦

[英]Trouble in ActiveX multi-thread invoke javascript callback routine

大家。 使用ATL进行ActiveX编程时遇到麻烦。 我尝试制作一个activex,它可以将文件从http服务器异步下载到本地文件夹,下载后会调用javascript回调函数。 我的解决方案:运行一个线程M来监视下载线程D,当D完成工作时,M将自己终止并调用IDispatch接口来调用javascript函数。 * ** * ** * ** * ** * ** *我的代码是: * ** * ** * ** * ** * ** *

/* javascript code */
funciton download() {
   var xfm = new ActiveXObject("XFileMngr.FileManager.1");
   xfm.download(
    'http://somedomain/somefile','localdev:\\folder\localfile',function(msg){alert(msg);});
}

/* C++ code */

// main routine
STDMETHODIMP CFileManager::download(BSTR url, BSTR local, VARIANT scriptCallback)
{
    CString csURL(url);
    CString csLocal(local);

    CAsyncDownload download;
    download.Download(this, csURL, csLocal, scriptCallback);

    return S_OK;
}

// parts of CAsyncDownload.h
typedef struct tagThreadData {
    CAsyncDownload* pThis;
} THREAD_DATA, *LPTHREAD_DATA;

class CAsyncDownload :
    public IBindStatusCallback
{
private:
    LPUNKNOWN pcaller;
    CString csRemoteFile;
    CString csLocalFile;
    CComPtr<IDispatch> spCallback;
public:
    void onDone(HRESULT hr);

    HRESULT Download(LPUNKNOWN caller, CString& csRemote, CString& csLocal, VARIANT callback);

    static DWORD __stdcall ThreadProc(void* param);
};
// parts of CAsyncDownload.cpp
void CAsyncDownload::onDone(HRESULT hr) {
    if(spCallback) {
        TRACE(TEXT("invoke callback function\n"));
        CComVariant vParams[1];
        vParams[0] = "callback is working!";

        DISPPARAMS params = { vParams, NULL, 1, 0 };

        HRESULT hr = spCallback->Invoke(0,
            IID_NULL,
            LOCALE_USER_DEFAULT,
            DISPATCH_METHOD,
            &params, NULL, NULL, NULL);

        if(FAILED(hr)) {
            CString csBuffer;
            csBuffer.Format(TEXT("invoke failed, result value: %d \n"),hr);
            TRACE(csBuffer);
        }else {
            TRACE(TEXT("invoke was successful\n"));
        }
    }
}

HRESULT CAsyncDownload::Download(LPUNKNOWN caller, CString& csRemote, CString& csLocal, VARIANT callback) {
    CoInitializeEx(NULL, COINIT_MULTITHREADED);

    csRemoteFile = csRemote;
    csLocalFile = csLocal;
    pcaller = caller;

    switch(callback.vt){
        case VT_DISPATCH:
        case VT_VARIANT:{
            spCallback = callback.pdispVal;
        }
        break;
        default:{
            spCallback = NULL;
        }
    }

    LPTHREAD_DATA pData = new THREAD_DATA;
    pData->pThis = this;

    // create monitor thread M
    HANDLE hThread = CreateThread(NULL, 0, ThreadProc, (void*)(pData), 0, NULL);

    if(!hThread) {
        delete pData;
        return HRESULT_FROM_WIN32(GetLastError());
    }

    WaitForSingleObject(hThread, INFINITE);
    CloseHandle(hThread);

    CoUninitialize();

    return S_OK;
}


DWORD __stdcall CAsyncDownload::ThreadProc(void* param) {
    LPTHREAD_DATA pData = (LPTHREAD_DATA)param;

    // here, we will create http download thread D
    // when download job is finish, call onDone method;

    pData->pThis->onDone(S_OK);

    delete pData;

    return 0;
}

** * ** * ** * ** * ** * *代码完成* ** * ** * ** * ** * ** * OK,以上是我的源代码的一部分,如果我在其中调用onDone方法子线程,我将获得OLE ERROR(-2147418113(8000FFFF)灾难性故障。)。 我错过了什么? 请帮我搞清楚。

IE的JavaScript引擎是单线程的,ATL的事件引发代码也是如此。 让子线程向创建ActiveX的线程发送消息(例如,如果有的话,发送到ActiceX窗口的句柄),然后引发事件。

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