c++ - 如何将 HTML 字符串加载到嵌入式 WebBrowser 控件？

转载作者：搜寻专家更新时间：2023-10-31 02:10:31

我知道网上有很多关于这个的文章，我试了很多。虽然我可以让我的浏览器加载互联网上的网页，但我无法设法让它从内存中加载 HTML。

大多数时候，下面的两种方法没有任何可见的效果；其他时候，他们会抛出错误。虽然其他人说“pPSI 和pHtmlDoc2 都没有指向有效对象”，但我不知道这是不是真的。我已经用注释标记了导致错误的行。

如果您想重现问题，我的问题末尾是完整的工作代码。

方法一

void WebBrowser::setHTML(const wchar_t *htmlSource) {
    HRESULT                   hr;

    IDispatch                 *pDispatch = 0;
    IHTMLDocument2            *pHtmlDoc2 = 0;
    IPersistStreamInit        *pPSI = 0;
    IStream                   *pStream = 0;
    HGLOBAL                   hHTMLContent;

    Navigate(L"about:blank");
    hr = webBrowser2->get_Document(&pDispatch);
    if (SUCCEEDED(hr) && pDispatch) hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void **)&pHtmlDoc2);
    //BSTR p = 0;
    //if (SUCCEEDED(hr)) hr = pHtmlDoc2->get_readyState(&p);

    if (SUCCEEDED(hr) && pHtmlDoc2) hr = pHtmlDoc2->QueryInterface(IID_IPersistStreamInit, (void **)&pPSI);


    // allocate global memory to copy the HTML content to
    hHTMLContent = ::GlobalAlloc(GMEM_MOVEABLE, (::wcslen(htmlSource) + 1) * sizeof(TCHAR));
    if (hHTMLContent)
    {
        wchar_t * p_content(static_cast<wchar_t *>(GlobalLock(hHTMLContent)));
        ::wcscpy(p_content, htmlSource);  // Debbug: p_content contains HTML string
        GlobalUnlock(hHTMLContent);

        // create a stream object based on the HTML content
        if (SUCCEEDED(hr) && pPSI) hr = ::CreateStreamOnHGlobal(hHTMLContent, TRUE, &pStream);
        {
            hr = pPSI->InitNew();         //////////// <- Sometime throw error.
            if (SUCCEEDED(hr)) hr = pPSI->Load(pStream); 
        }
    }
    if (pStream) pStream->Release();
    if (pPSI) pPSI->Release();
    if (pHtmlDoc2) pHtmlDoc2->Release();
    if (pDispatch) pDispatch->Release();

}

错误:

Exception thrown at 0x51539FB1 (mshtml.dll) in Test.exe: 0xC0000005: Access violation reading location 0x00000030

方法二

这个修改自this article在 CodeProject 上。在那个源代码中，它工作得很好，但是当我尝试适应我的代码时它不起作用:

void WebBrowser::setHTML2(const wchar_t *htmlSource) {
    HRESULT                   hr;

    IDispatch                 *pDispatch = 0;
    IHTMLDocument2            *pHtmlDoc2 = 0;

    this->Navigate(L"about:blank");
    hr = this->webBrowser2->get_Document(&pDispatch);
    if (SUCCEEDED(hr) && pDispatch) hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void **)&pHtmlDoc2);
    if (SUCCEEDED(hr) && pHtmlDoc2)
    {
        BSTR bstr = SysAllocString(htmlSource);
        SAFEARRAY *psaStrings = SafeArrayCreateVector(VT_VARIANT, 0, 1);
        if (psaStrings)
        {
            VARIANT *param;
            hr = SafeArrayAccessData(psaStrings, (LPVOID*)&param);
            if (SUCCEEDED(hr) && param)
            {
                param->vt = VT_BSTR;
                param->bstrVal = bstr;
                //if (SUCCEEDED(hr)) hr = SafeArrayUnaccessData(psaStrings);
                if (SUCCEEDED(hr))
                {
                    hr = pHtmlDoc2->write(psaStrings); //////////// <- Sometime throw error.
                }
            }

            SafeArrayDestroy(psaStrings);
        }
    }
    if (pHtmlDoc2) pHtmlDoc2->Release();
    if (pDispatch) pDispatch->Release();
}

错误:

Exception thrown at 0x51577F2E (mshtml.dll) in Test.exe: 0xC0000005: Access violation reading location 0x000002C4

可能的第三种方法，Loading HTML content from a Stream来自 Microsoft，建议我从 DWebBrowserEvents2::DocumentComplete 事件的流中加载，我已经尝试过但未能弄清楚如何实现。

完整源代码

下面是完整的代码。我创建一个新的 Win32 项目并创建/修改以下文件:

浏览器.h

#include <comdef.h>
#include <Exdisp.h>
#include <ExDispid.h>
#include <MsHTML.h>
#include <Mshtmhst.h>
#include <string>
#include <tchar.h>
#include <Windows.h>

using namespace std;

class WebBrowser :
    public IOleClientSite,
    public IOleInPlaceSite,
    public IStorage
{

public:

    WebBrowser(HWND hWndParent);

    bool CreateBrowser();

    void SetText(const wchar_t* t);

    void setHTML(const wchar_t *htmlSource);
    void setHTML2(const wchar_t *htmlSource);

    RECT PixelToHiMetric(const RECT& _rc);

    virtual void SetRect(const RECT& _rc);

    // ----- Control methods -----

    void GoBack();

    void GoForward();

    void Refresh();

    void Navigate(wstring szUrl);

    // ----- IUnknown -----

    virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid,
        void**ppvObject) override;

    virtual ULONG STDMETHODCALLTYPE AddRef(void);

    virtual ULONG STDMETHODCALLTYPE Release(void);

    // ---------- IOleWindow ----------

    virtual HRESULT STDMETHODCALLTYPE GetWindow(
        __RPC__deref_out_opt HWND *phwnd) override;

    virtual HRESULT STDMETHODCALLTYPE ContextSensitiveHelp(
        BOOL fEnterMode) override;

    // ---------- IOleInPlaceSite ----------

    virtual HRESULT STDMETHODCALLTYPE CanInPlaceActivate(void) override;

    virtual HRESULT STDMETHODCALLTYPE OnInPlaceActivate(void) override;

    virtual HRESULT STDMETHODCALLTYPE OnUIActivate(void) override;

    virtual HRESULT STDMETHODCALLTYPE GetWindowContext(
        __RPC__deref_out_opt IOleInPlaceFrame **ppFrame,
        __RPC__deref_out_opt IOleInPlaceUIWindow **ppDoc,
        __RPC__out LPRECT lprcPosRect,
        __RPC__out LPRECT lprcClipRect,
        __RPC__inout LPOLEINPLACEFRAMEINFO lpFrameInfo) override;

    virtual HRESULT STDMETHODCALLTYPE Scroll(
        SIZE scrollExtant) override;

    virtual HRESULT STDMETHODCALLTYPE OnUIDeactivate(
        BOOL fUndoable) override;

    virtual HWND GetControlWindow();

    virtual HRESULT STDMETHODCALLTYPE OnInPlaceDeactivate(void) override;

    virtual HRESULT STDMETHODCALLTYPE DiscardUndoState(void) override;

    virtual HRESULT STDMETHODCALLTYPE DeactivateAndUndo(void) override;

    virtual HRESULT STDMETHODCALLTYPE OnPosRectChange(
        __RPC__in LPCRECT lprcPosRect) override;

    // ---------- IOleClientSite ----------

    virtual HRESULT STDMETHODCALLTYPE SaveObject(void) override;

    virtual HRESULT STDMETHODCALLTYPE GetMoniker(
        DWORD dwAssign,
        DWORD dwWhichMoniker,
        __RPC__deref_out_opt IMoniker **ppmk) override;

    virtual HRESULT STDMETHODCALLTYPE GetContainer(
        __RPC__deref_out_opt IOleContainer **ppContainer) override;

    virtual HRESULT STDMETHODCALLTYPE ShowObject(void) override;
    virtual HRESULT STDMETHODCALLTYPE OnShowWindow(
        BOOL fShow) override;

    virtual HRESULT STDMETHODCALLTYPE RequestNewObjectLayout(void) override;

    // ----- IStorage -----

    virtual HRESULT STDMETHODCALLTYPE CreateStream(
        __RPC__in_string const OLECHAR *pwcsName,
        DWORD grfMode,
        DWORD reserved1,
        DWORD reserved2,
        __RPC__deref_out_opt IStream **ppstm) override;

    virtual HRESULT STDMETHODCALLTYPE OpenStream(
        const OLECHAR *pwcsName,
        void *reserved1,
        DWORD grfMode,
        DWORD reserved2,
        IStream **ppstm) override;

    virtual HRESULT STDMETHODCALLTYPE CreateStorage(
        __RPC__in_string const OLECHAR *pwcsName,
        DWORD grfMode,
        DWORD reserved1,
        DWORD reserved2,
        __RPC__deref_out_opt IStorage **ppstg) override;

    virtual HRESULT STDMETHODCALLTYPE OpenStorage(
        __RPC__in_opt_string const OLECHAR *pwcsName,
        __RPC__in_opt IStorage *pstgPriority,
        DWORD grfMode,
        __RPC__deref_opt_in_opt SNB snbExclude,
        DWORD reserved,
        __RPC__deref_out_opt IStorage **ppstg) override;

    virtual HRESULT STDMETHODCALLTYPE CopyTo(
        DWORD ciidExclude,
        const IID *rgiidExclude,
        __RPC__in_opt  SNB snbExclude,
        IStorage *pstgDest) override;

    virtual HRESULT STDMETHODCALLTYPE MoveElementTo(
        __RPC__in_string const OLECHAR *pwcsName,
        __RPC__in_opt IStorage *pstgDest,
        __RPC__in_string const OLECHAR *pwcsNewName,
        DWORD grfFlags) override;

    virtual HRESULT STDMETHODCALLTYPE Commit(
        DWORD grfCommitFlags) override;

    virtual HRESULT STDMETHODCALLTYPE Revert(void) override;

    virtual HRESULT STDMETHODCALLTYPE EnumElements(
        DWORD reserved1,
        void *reserved2,
        DWORD reserved3,
        IEnumSTATSTG **ppenum) override;

    virtual HRESULT STDMETHODCALLTYPE DestroyElement(
        __RPC__in_string const OLECHAR *pwcsName) override;

    virtual HRESULT STDMETHODCALLTYPE RenameElement(
        __RPC__in_string const OLECHAR *pwcsOldName,
        __RPC__in_string const OLECHAR *pwcsNewName) override;

    virtual HRESULT STDMETHODCALLTYPE SetElementTimes(
        __RPC__in_opt_string const OLECHAR *pwcsName,
        __RPC__in_opt const FILETIME *pctime,
        __RPC__in_opt const FILETIME *patime,
        __RPC__in_opt const FILETIME *pmtime) override;

    virtual HRESULT STDMETHODCALLTYPE SetClass(
        __RPC__in REFCLSID clsid) override;
    virtual HRESULT STDMETHODCALLTYPE SetStateBits(
        DWORD grfStateBits,
        DWORD grfMask) override;

    virtual HRESULT STDMETHODCALLTYPE Stat(
        __RPC__out STATSTG *pstatstg,
        DWORD grfStatFlag) override;

protected:

    IOleObject* oleObject;
    IOleInPlaceObject* oleInPlaceObject;

    IWebBrowser2* webBrowser2;

    LONG iComRefCount;

    RECT rObject;

    HWND hWndParent;
    HWND hWndControl;

};

浏览器.cpp

#include "stdafx.h"
#include "Browser.h"



namespace tkString
{
    wchar_t* Format(const wchar_t* format, ...)
    {
        va_list args;
        va_start(args, format);

        wchar_t *w = NULL;
        int len = _vsnwprintf(NULL, 0, format, args) + 1;
        if (len > 0)
        {
            w = new wchar_t[len];
            w[0] = 0;
            _vsnwprintf_s(w, len, len, format, args);
        }
        va_end(args);

        return w;
    }
}


void WebBrowser::SetText(const wchar_t* t)
{
    const wchar_t* html = L"<html><head><meta http-equiv='x-ua-compatible' content='IE=edge'></head><body><code>%ls</code></body></html>";

    if (t)
    {
        wchar_t *w = tkString::Format(html, t);
        setHTML(w);
        //setHTML2(w);
        delete[] w;
    }
    else this->Navigate(L"https://google.com.vn");
}

void WebBrowser::setHTML(const wchar_t *htmlSource) {
    HRESULT                   hr;

    IDispatch                 *pDispatch = 0;
    IHTMLDocument2            *pHtmlDoc2 = 0;
    IPersistStreamInit        *pPSI = 0;
    IStream                   *pStream = 0;
    HGLOBAL                   hHTMLContent;

    Navigate(L"about:blank");
    hr = webBrowser2->get_Document(&pDispatch);
    if (SUCCEEDED(hr) && pDispatch) hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void **)&pHtmlDoc2);
    //BSTR p = 0;
    //if (SUCCEEDED(hr)) hr = pHtmlDoc2->get_readyState(&p);

    if (SUCCEEDED(hr) && pHtmlDoc2) hr = pHtmlDoc2->QueryInterface(IID_IPersistStreamInit, (void **)&pPSI);


    // allocate global memory to copy the HTML content to
    hHTMLContent = ::GlobalAlloc(GMEM_MOVEABLE, (::wcslen(htmlSource) + 1) * sizeof(TCHAR));
    if (hHTMLContent)
    {
        wchar_t * p_content(static_cast<wchar_t *>(GlobalLock(hHTMLContent)));
        ::wcscpy(p_content, htmlSource);
        GlobalUnlock(hHTMLContent);

        // create a stream object based on the HTML content
        if (SUCCEEDED(hr) && pPSI) hr = ::CreateStreamOnHGlobal(hHTMLContent, TRUE, &pStream);

        if (SUCCEEDED(hr) && pStream) hr = pPSI->InitNew();
        if (SUCCEEDED(hr)) hr = pPSI->Load(pStream);
    }
    if (pStream) pStream->Release();
    if (pPSI) pPSI->Release();
    if (pHtmlDoc2) pHtmlDoc2->Release();
    if (pDispatch) pDispatch->Release();

}

void WebBrowser::setHTML2(const wchar_t *htmlSource) {
    HRESULT                   hr;

    IDispatch                 *pDispatch = 0;
    IHTMLDocument2            *pHtmlDoc2 = 0;

    this->Navigate(L"about:blank");
    hr = this->webBrowser2->get_Document(&pDispatch);
    if (SUCCEEDED(hr) && pDispatch) hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void **)&pHtmlDoc2);
    if (SUCCEEDED(hr) && pHtmlDoc2)
    {
        BSTR bstr = SysAllocString(htmlSource);
        SAFEARRAY *psaStrings = SafeArrayCreateVector(VT_VARIANT, 0, 1);
        if (psaStrings)
        {
            VARIANT *param;
            hr = SafeArrayAccessData(psaStrings, (LPVOID*)&param);
            if (SUCCEEDED(hr) && param)
            {
                param->vt = VT_BSTR;
                param->bstrVal = bstr;
                //if (SUCCEEDED(hr)) hr = SafeArrayUnaccessData(psaStrings);
                if (SUCCEEDED(hr)) hr = pHtmlDoc2->write(psaStrings);
            }

            SafeArrayDestroy(psaStrings);
        }
    }
    if (pHtmlDoc2) pHtmlDoc2->Release();
    if (pDispatch) pDispatch->Release();
}


WebBrowser::WebBrowser(HWND _hWndParent)
{
    iComRefCount = 0;
    ::SetRect(&rObject, 0, 0, 600, 400);
    hWndParent = _hWndParent;

    if (CreateBrowser() == FALSE)
    {
        return;
    }
    webBrowser2->put_Visible(TRUE);
    ShowWindow(GetControlWindow(), SW_SHOW);

    this->Navigate(_T("about:blank"));
}

bool WebBrowser::CreateBrowser()
{
    HRESULT hr;
    hr = ::OleCreate(CLSID_WebBrowser,
        IID_IOleObject, OLERENDER_DRAW, 0, this, this,
        (void**)&oleObject);

    if (FAILED(hr))
    {
        MessageBox(NULL, _T("Cannot create oleObject CLSID_WebBrowser"),
            _T("Error"),
            MB_ICONERROR);
        return FALSE;
    }

    hr = oleObject->SetClientSite(this);
    hr = OleSetContainedObject(oleObject, TRUE);

    RECT posRect;
    ::SetRect(&rObject, 0, 0, 600, 400);
    hr = oleObject->DoVerb(OLEIVERB_INPLACEACTIVATE,
        NULL, this, -1, hWndParent, &posRect);
    if (FAILED(hr))
    {
        MessageBox(NULL, _T("oleObject->DoVerb() failed"),
            _T("Error"),
            MB_ICONERROR);
        return FALSE;
    }

    hr = oleObject->QueryInterface(&webBrowser2);
    if (FAILED(hr))
    {
        MessageBox(NULL, _T("oleObject->QueryInterface(&webBrowser2) failed"),
            _T("Error"),
            MB_ICONERROR);
        return FALSE;
    }

    return TRUE;
}

RECT WebBrowser::PixelToHiMetric(const RECT& _rc)
{
    static bool s_initialized = false;
    static int s_pixelsPerInchX, s_pixelsPerInchY;
    if (!s_initialized)
    {
        HDC hdc = ::GetDC(0);
        s_pixelsPerInchX = ::GetDeviceCaps(hdc, LOGPIXELSX);
        s_pixelsPerInchY = ::GetDeviceCaps(hdc, LOGPIXELSY);
        ::ReleaseDC(0, hdc);
        s_initialized = true;
    }

    RECT rc;
    rc.left = MulDiv(2540, _rc.left, s_pixelsPerInchX);
    rc.top = MulDiv(2540, _rc.top, s_pixelsPerInchY);
    rc.right = MulDiv(2540, _rc.right, s_pixelsPerInchX);
    rc.bottom = MulDiv(2540, _rc.bottom, s_pixelsPerInchY);
    return rc;
}

void WebBrowser::SetRect(const RECT& _rc)
{
    rObject = _rc;

    {
        RECT hiMetricRect = PixelToHiMetric(rObject);
        SIZEL sz;
        sz.cx = hiMetricRect.right - hiMetricRect.left;
        sz.cy = hiMetricRect.bottom - hiMetricRect.top;
        oleObject->SetExtent(DVASPECT_CONTENT, &sz);
    }

    if (oleInPlaceObject != 0)
    {
        oleInPlaceObject->SetObjectRects(&rObject, &rObject);
    }
}

// ----- Control methods -----

void WebBrowser::GoBack()
{
    this->webBrowser2->GoBack();
}

void WebBrowser::GoForward()
{
    this->webBrowser2->GoForward();
}

void WebBrowser::Refresh()
{
    this->webBrowser2->Refresh();
}

void WebBrowser::Navigate(wstring szUrl)
{
    bstr_t url(szUrl.c_str());
    variant_t flags(0x02u); //navNoHistory
    this->webBrowser2->Navigate(url, &flags, 0, 0, 0);
}

// ----- IUnknown -----

HRESULT STDMETHODCALLTYPE WebBrowser::QueryInterface(REFIID riid,
    void**ppvObject)
{
    if (riid == __uuidof(IUnknown))
    {
        (*ppvObject) = static_cast<IOleClientSite*>(this);
    }
    else if (riid == __uuidof(IOleInPlaceSite))
    {
        (*ppvObject) = static_cast<IOleInPlaceSite*>(this);
    }
    else
    {
        return E_NOINTERFACE;
    }

    AddRef();
    return S_OK;
}

ULONG STDMETHODCALLTYPE WebBrowser::AddRef(void)
{
    iComRefCount++;
    return iComRefCount;
}

ULONG STDMETHODCALLTYPE WebBrowser::Release(void)
{
    iComRefCount--;
    return iComRefCount;
}

// ---------- IOleWindow ----------

HRESULT STDMETHODCALLTYPE WebBrowser::GetWindow(
    __RPC__deref_out_opt HWND *phwnd)
{
    (*phwnd) = hWndParent;
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::ContextSensitiveHelp(
    BOOL fEnterMode)
{
    return E_NOTIMPL;
}

// ---------- IOleInPlaceSite ----------

HRESULT STDMETHODCALLTYPE WebBrowser::CanInPlaceActivate(void)
{
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OnInPlaceActivate(void)
{
    OleLockRunning(oleObject, TRUE, FALSE);
    oleObject->QueryInterface(&oleInPlaceObject);
    oleInPlaceObject->SetObjectRects(&rObject, &rObject);

    return S_OK;

}

HRESULT STDMETHODCALLTYPE WebBrowser::OnUIActivate(void)
{
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::GetWindowContext(
    __RPC__deref_out_opt IOleInPlaceFrame **ppFrame,
    __RPC__deref_out_opt IOleInPlaceUIWindow **ppDoc,
    __RPC__out LPRECT lprcPosRect,
    __RPC__out LPRECT lprcClipRect,
    __RPC__inout LPOLEINPLACEFRAMEINFO lpFrameInfo)
{
    HWND hwnd = hWndParent;

    (*ppFrame) = NULL;
    (*ppDoc) = NULL;
    (*lprcPosRect).left = rObject.left;
    (*lprcPosRect).top = rObject.top;
    (*lprcPosRect).right = rObject.right;
    (*lprcPosRect).bottom = rObject.bottom;
    *lprcClipRect = *lprcPosRect;

    lpFrameInfo->fMDIApp = false;
    lpFrameInfo->hwndFrame = hwnd;
    lpFrameInfo->haccel = NULL;
    lpFrameInfo->cAccelEntries = 0;

    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::Scroll(
    SIZE scrollExtant)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OnUIDeactivate(
    BOOL fUndoable)
{
    return S_OK;
}

HWND WebBrowser::GetControlWindow()
{
    if (hWndControl != 0)
        return hWndControl;

    if (oleInPlaceObject == 0)
        return 0;

    oleInPlaceObject->GetWindow(&hWndControl);
    return hWndControl;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OnInPlaceDeactivate(void)
{
    hWndControl = 0;
    oleInPlaceObject = 0;

    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::DiscardUndoState(void)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::DeactivateAndUndo(void)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OnPosRectChange(
    __RPC__in LPCRECT lprcPosRect)
{
    return E_NOTIMPL;
}

// ---------- IOleClientSite ----------

HRESULT STDMETHODCALLTYPE WebBrowser::SaveObject(void)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::GetMoniker(
    DWORD dwAssign,
    DWORD dwWhichMoniker,
    __RPC__deref_out_opt IMoniker **ppmk)
{
    if ((dwAssign == OLEGETMONIKER_ONLYIFTHERE) &&
        (dwWhichMoniker == OLEWHICHMK_CONTAINER))
        return E_FAIL;

    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::GetContainer(
    __RPC__deref_out_opt IOleContainer **ppContainer)
{
    return E_NOINTERFACE;
}

HRESULT STDMETHODCALLTYPE WebBrowser::ShowObject(void)
{
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OnShowWindow(
    BOOL fShow)
{
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::RequestNewObjectLayout(void)
{
    return E_NOTIMPL;
}

// ----- IStorage -----

HRESULT STDMETHODCALLTYPE WebBrowser::CreateStream(
    __RPC__in_string const OLECHAR *pwcsName,
    DWORD grfMode,
    DWORD reserved1,
    DWORD reserved2,
    __RPC__deref_out_opt IStream **ppstm)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OpenStream(
    const OLECHAR *pwcsName,
    void *reserved1,
    DWORD grfMode,
    DWORD reserved2,
    IStream **ppstm)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::CreateStorage(
    __RPC__in_string const OLECHAR *pwcsName,
    DWORD grfMode,
    DWORD reserved1,
    DWORD reserved2,
    __RPC__deref_out_opt IStorage **ppstg)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::OpenStorage(
    __RPC__in_opt_string const OLECHAR *pwcsName,
    __RPC__in_opt IStorage *pstgPriority,
    DWORD grfMode,
    __RPC__deref_opt_in_opt SNB snbExclude,
    DWORD reserved,
    __RPC__deref_out_opt IStorage **ppstg)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::CopyTo(
    DWORD ciidExclude,
    const IID *rgiidExclude,
    __RPC__in_opt  SNB snbExclude,
    IStorage *pstgDest)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::MoveElementTo(
    __RPC__in_string const OLECHAR *pwcsName,
    __RPC__in_opt IStorage *pstgDest,
    __RPC__in_string const OLECHAR *pwcsNewName,
    DWORD grfFlags)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::Commit(
    DWORD grfCommitFlags)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::Revert(void)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::EnumElements(
    DWORD reserved1,
    void *reserved2,
    DWORD reserved3,
    IEnumSTATSTG **ppenum)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::DestroyElement(
    __RPC__in_string const OLECHAR *pwcsName)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::RenameElement(
    __RPC__in_string const OLECHAR *pwcsOldName,
    __RPC__in_string const OLECHAR *pwcsNewName)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::SetElementTimes(
    __RPC__in_opt_string const OLECHAR *pwcsName,
    __RPC__in_opt const FILETIME *pctime,
    __RPC__in_opt const FILETIME *patime,
    __RPC__in_opt const FILETIME *pmtime)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::SetClass(
    __RPC__in REFCLSID clsid)
{
    return S_OK;
}

HRESULT STDMETHODCALLTYPE WebBrowser::SetStateBits(
    DWORD grfStateBits,
    DWORD grfMask)
{
    return E_NOTIMPL;
}

HRESULT STDMETHODCALLTYPE WebBrowser::Stat(
    __RPC__out STATSTG *pstatstg,
    DWORD grfStatFlag)
{
    return E_NOTIMPL;
}

Win32Project1.cpp

#include "stdafx.h"
#include "Win32Project1.h"
#include "Browser.h"

HWND mainHWND;
WebBrowser* myBrowser = NULL;

#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE hInst;                                // current instance
WCHAR szTitle[MAX_LOADSTRING];                  // The title bar text
WCHAR szWindowClass[MAX_LOADSTRING];            // the main window class name

ATOM                MyRegisterClass(HINSTANCE hInstance);
BOOL                InitInstance(HINSTANCE, int);
LRESULT CALLBACK    WndProc(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK    About(HWND, UINT, WPARAM, LPARAM);

int APIENTRY wWinMain(_In_ HINSTANCE hInstance,
                     _In_opt_ HINSTANCE hPrevInstance,
                     _In_ LPWSTR    lpCmdLine,
                     _In_ int       nCmdShow)
{
    UNREFERENCED_PARAMETER(hPrevInstance);
    UNREFERENCED_PARAMETER(lpCmdLine);
    OleInitialize(NULL);

    LoadStringW(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
    LoadStringW(hInstance, IDC_WIN32PROJECT1, szWindowClass, MAX_LOADSTRING);
    MyRegisterClass(hInstance);

    if (!InitInstance (hInstance, nCmdShow))
    {
        return FALSE;
    }
    myBrowser = new WebBrowser(mainHWND);
    //myBrowser->Navigate(L"https://google.com.vn");
    myBrowser->SetText(L"Hello!");

    HACCEL hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_WIN32PROJECT1));

    MSG msg;

    while (GetMessage(&msg, nullptr, 0, 0))
    {
        if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }

    return (int) msg.wParam;
}

ATOM MyRegisterClass(HINSTANCE hInstance)
{
    WNDCLASSEXW wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc    = WndProc;
    wcex.cbClsExtra     = 0;
    wcex.cbWndExtra     = 0;
    wcex.hInstance      = hInstance;
    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_WIN32PROJECT1));
    wcex.hCursor        = LoadCursor(nullptr, IDC_ARROW);
    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);
    wcex.lpszMenuName   = MAKEINTRESOURCEW(IDC_WIN32PROJECT1);
    wcex.lpszClassName  = szWindowClass;
    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));

    return RegisterClassExW(&wcex);
}

BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
   hInst = hInstance; // Store instance handle in our global variable

   mainHWND = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, nullptr, nullptr, hInstance, nullptr);

   if (!mainHWND)
   {
      return FALSE;
   }

   ShowWindow(mainHWND, nCmdShow);
   UpdateWindow(mainHWND);

   return TRUE;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
    case WM_COMMAND:
        {
            int wmId = LOWORD(wParam);
            // Parse the menu selections:
            switch (wmId)
            {
            case IDM_ABOUT:
                DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
                break;
            case IDM_EXIT:
                DestroyWindow(hWnd);
                break;
            default:
                return DefWindowProc(hWnd, message, wParam, lParam);
            }
        }
        break;
    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hWnd, &ps);
            // TODO: Add any drawing code that uses hdc here...
            EndPaint(hWnd, &ps);
        }
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}

INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    // Removed
    return (INT_PTR)FALSE;
}

Visual Studio 创建的其他源文件保持不变。

问题

什么问题导致我的程序无法加载 HTML 字符串，我该如何解决？或者您是否有任何工作示例(没有 MFC 或 ATL)将 HTML 字符串加载到 WebBrowser？

注意:我知道我可以将 HTML 字符串写入硬盘并将文件路径传递给浏览器，但我根本不想涉及硬盘。

注意 2: 为了赢得赏金，请提供一个完整的工作代码示例，尽可能多地使用我的代码。浏览器应成功加载 HTML 字符串。即使它正在加载在线网页，它也应该停止处理这个新命令。

最佳答案

   Navigate(L"about:blank");

发布的源代码没有很好地说明问题。它没有显示错误，但也没有“你好”。只有通过省略 Navigate() 调用，它才接近于因 nullptr 错误而失败。代码还没有完成，它缺少捕获 DocumentComplete 事件所需的管道。只有此事件被触发后，WebBrowser::setHtml() 中的代码才能工作。

让 WebBrowser 类实现 IDispatch 和 IUnknown 接口(interface):

class WebBrowser :
    public IDispatch,
    public IUnknown,
    public IOleClientSite,
    public IOleInPlaceSite,
    public IStorage
{
private:
    HRESULT OnCompleted(DISPPARAMS* args);
    wchar_t* htmlSource;
    IConnectionPoint* callback;
    DWORD eventCookie;
    // etc...
};

注意 htmlSource 变量现在如何成为类成员，字符串需要存储到 DocumentComplete 事件触发。

我们需要实现 IDispatch。这很容易做到，我将代码内联:

// ---------- IDispatch ----------
HRESULT GetTypeInfoCount(UINT *pctinfo) {  return E_FAIL; }
HRESULT GetTypeInfo(UINT, LCID, ITypeInfo **) { return E_FAIL; }
HRESULT GetIDsOfNames(REFIID riid, LPOLESTR *rgszNames, UINT cNames, LCID lcid, DISPID *rgDispId) { return E_FAIL; }

HRESULT Invoke(DISPID dispIdMember, REFIID, LCID, WORD,
    DISPPARAMS *pDispParams, VARIANT *pVarResult,
    EXCEPINFO*, UINT*) {
    if (dispIdMember == DISPID_DOCUMENTCOMPLETE) return OnCompleted(pDispParams);
    else return S_OK;
}

QueryInterface() 需要调整:

HRESULT STDMETHODCALLTYPE WebBrowser::QueryInterface(REFIID riid, void**ppvObject)
{
    if      (riid == __uuidof(IUnknown))        *ppvObject = static_cast<IUnknown*>(this);
    else if (riid == __uuidof(IDispatch))       *ppvObject = static_cast<IDispatch*>(this);
    else if (riid == __uuidof(IOleClientSite))  *ppvObject = static_cast<IOleClientSite*>(this);
    else if (riid == __uuidof(IOleInPlaceSite)) *ppvObject = static_cast<IOleInPlaceSite*>(this);
    else
        return E_NOINTERFACE;
    AddRef();
    return S_OK;
}

构造函数需要订阅事件接口(interface):

WebBrowser::WebBrowser(HWND _hWndParent)
{
    //...
    // appended:
    htmlSource = nullptr;
    IConnectionPointContainer* container = nullptr;
    webBrowser2->QueryInterface(IID_IConnectionPointContainer, (void**)&container);
    container->FindConnectionPoint(__uuidof(DWebBrowserEvents2), &callback);
    IUnknown* punk = nullptr;
    this->QueryInterface(IID_IUnknown, (void**)&punk);
    callback->Advise(punk, &eventCookie);
    punk->Release();
    container->Release();
}

setText() 函数变得非常简单，我们根本不用担心 setHtml()。我们只需设置 htmlSource 成员，这样我们就知道在 DocumentComplete 事件触发时要做什么:

void WebBrowser::SetText(const wchar_t* t)
{
    const wchar_t* html = L"<html><head><meta http-equiv='x-ua-compatible' content='IE=edge'></head><body><code>%ls</code></body></html>";
    if (htmlSource) delete[] htmlSource;
    htmlSource = tkString::Format(html, t);
    this->Navigate(L"about::blank");
}

最后添加的函数在 DocumentComplete 事件触发时运行。大部分代码已从 setHtml 中移出:

HRESULT WebBrowser::OnCompleted(DISPPARAMS* args) {
    HRESULT                   hr;

    IDispatch                 *pDispatch = 0;
    IHTMLDocument2            *pHtmlDoc2 = 0;
    IPersistStreamInit        *pPSI = 0;
    IStream                   *pStream = 0;
    HGLOBAL                   hHTMLContent;


    if (!htmlSource) return S_OK;
    hr = webBrowser2->get_Document(&pDispatch);
    if (SUCCEEDED(hr) && pDispatch) hr = pDispatch->QueryInterface(IID_IHTMLDocument2, (void **)&pHtmlDoc2);
    if (SUCCEEDED(hr) && pHtmlDoc2) hr = pHtmlDoc2->QueryInterface(IID_IPersistStreamInit, (void **)&pPSI);


    // allocate global memory to copy the HTML content to
    hHTMLContent = ::GlobalAlloc(GMEM_MOVEABLE, (::wcslen(htmlSource) + 1) * sizeof(TCHAR));
    if (hHTMLContent)
    {
        wchar_t * p_content(static_cast<wchar_t *>(GlobalLock(hHTMLContent)));
        ::wcscpy(p_content, htmlSource);
        GlobalUnlock(hHTMLContent);

        // create a stream object based on the HTML content
        if (SUCCEEDED(hr) && pPSI) hr = ::CreateStreamOnHGlobal(hHTMLContent, TRUE, &pStream);

        if (SUCCEEDED(hr) && pStream) hr = pPSI->InitNew();
        if (SUCCEEDED(hr)) hr = pPSI->Load(pStream);
    }
    if (pStream) pStream->Release();
    if (pPSI) pPSI->Release();
    if (pHtmlDoc2) pHtmlDoc2->Release();
    if (pDispatch) pDispatch->Release();
    delete[] htmlSource;
    htmlSource = nullptr;
    return S_OK;
}

我会将适当的清理留作//待办事项。现在运行这段代码会产生预期的结果:

关于c++ - 如何将 HTML 字符串加载到嵌入式 WebBrowser 控件？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45103166/

文章推荐： c++ - QTableView + QAbstractTableModel : Move rows via drag'n'drop

文章推荐： c++ - 无法初始化初始化列表之外的字段

文章推荐： c++ - 检查类型 T 是否有成员函数 SFINAE 的任何重载

文章推荐： c++ - 将函数地址转换为 UINTPTR_T 给我不正确的结果

.net - 在sharepoint中使用SPListCollection.Add方法(字符串，字符串，字符串，字符串，Int32，字符串，SPListTemplate.QuickLaunchOptions)
如何使用 SPListCollection.Add(String, String, String, String, Int32, String, SPListTemplate.QuickLaunchO
C++ 字符串 != 字符串
我刚刚开始使用 C++ 并且对 C# 有一些经验，所以我有一些一般的编程经验。然而，似乎我马上就被击落了。我试过在谷歌上寻找，以免浪费任何人的时间，但没有结果。 int main(int argc,
Java 8 : Converting Map>到映射<字符串，字符串[]>
这个问题已经有答案了: In Java 8 how do I transform a Map to another Map using a lambda? (8 个回答) Convert a Map>
node.js - "Type ' 字符串 |字符串[] ' is not assignable to type ' 字符串'
我正在使用 node + typescript 和集成的 swagger 进行 API 调用。我 Swagger 提出以下要求 http://localhost:3033/employees/sear
C++ 映射<字符串， vector <对<字符串，字符串>>> : adding a mapping to an empty vector?
我是 C++ 容器模板的新手。我收集了一些记录。每条记录都有一个唯一的名称，以及一个字段/值对列表。将按名称访问记录。字段/值对的顺序很重要。因此我设计如下: typedef string
java - 谁能帮我创建方法？ mystring.replacefirst(字符串,字符串);并替换(自，直到，字符串)；对于j2me，请
我需要这两种方法，但j2me没有，我找到了一个replaceall();但这是 replaceall(string,string,string); 第二个方法是SringBuffer但在j2me中它没
.net - 字符串 vs 字符串 - 区分大小写的联合
If string is an alias of String in the .net framework为什么会发生这种情况，我应该如何解释它: type JustAString = string
python - 考虑顺序如何检查列表(字符串)是否包含另一个列表(字符串)
我有两个列表(或字符串):一个大，另一个小。我想检查较大的(A)是否包含小的(B)。我的期望如下: 案例 1. B 是 A 的子集 A = [1,2,3] B = [1,2] contains(A
javascript - Jquery 字符串 + 对象 + 字符串
我有一个似乎无法解决的小问题。这里...我有一个像这样创建的输入... var input = $(''); 如果我这样做......一切都很好 $(this).append(input); 如果我
c# - ienumerable <字符串>到列表<字符串>
我有以下代码片段 string[] lines = objects.Split(new string[] { "\r\n", "\n" }, StringSplitOptions.No
Java printf(字符串、Val、字符串)
这可能真的很简单，但我已经坚持了一段时间了。我正在尝试输出一个字符串，然后输出一个带有两位小数的 double ，后跟另一个字符串，这是我的代码。 System.out.printf("成本:%.2
firebase - Cloud Firestore 字符串 >= 字符串
以下是 Cloud Firestore 列表查询中的示例之一 citiesRef.where("state", ">=", "CA").where("state", "= 字符串，我们在Stack O
javascript - if(字符串.包含(字符串))。那可能吗？
我正在尝试检查一个字符串是否包含在另一个字符串中。后面的代码非常简单。我怎样才能在 jquery 中做到这一点？ function deleteRow(locName, locID) { if
C++ 字符串 (int) + 字符串 (int)
这个问题在这里已经有了答案: How to implement big int in C++ (14 个答案) 关闭 9 年前。我有 2 个字符串，都只包含数字。这些数字大于 uint64_t 的
java - 带有自定义转换器的推土机双向映射(字符串，字符串)不可能吗？
我有一个带有自定义转换器的 Dozer 映射: com.xyz.Customer com.xyz.CustomerDAO customerName
java - 字符串 a == 字符串 b 的规则
这个问题在这里已经有了答案: How do I compare strings in Java? (23 个回答) 关闭 6 年前。我想了解字符串池的工作原理以及一个字符串等于另一个字符串的规则是
Swift 字符串 vs. 字符串!与字符串？
我已阅读 this问题和其他一些问题。但它们与我的问题有些无关对于 UILabel 如果你不指定 ? 或 ! 你会得到这样的错误: @IBOutlet property has non-option
c - 字符串 [x] 与 *字符串++
这两种方法中哪一种在理论上更快，为什么？ (指向字符串的指针必须是常量。) destination[count] 和 *destination++ 之间的确切区别是什么？ destination[co
.net - String.Format与“字符串” +“字符串”还是StringBuilder？
This question already has answers here: Closed 11 years ago. Possible Duplicates: Is String.Format a
java - 流<字符串> 到映射<字符串、整数>
我有一个Stream一个文件的，现在我想将相同的单词组合成 Map这很重要，这个词在 Stream 中出现的频率. 我知道我必须使用 collect(Collectors.groupingBy(..)

搜寻专家

个人简介

我是一名优秀的程序员,十分优秀！

作者热门文章

滴滴打车优惠券免费领取

全站热门文章

首页

博学

6Ren·AI

商城

c++ - 如何将 HTML 字符串加载到嵌入式 WebBrowser 控件？

方法一

方法二

完整源代码

浏览器.h

浏览器.cpp

Win32Project1.cpp

问题