使用IHTMLDocument2分析Html

利用CWebBrowser2获取IHTMLDocument2接口，IHTMLDocument2接口是mshtml中最重要的接口之一，取得这个接口，就可以开始分析html代码

下面的代码将获取特定的html 文本标签

// 从ctlBrowser当前html文档选中区域中获取名为strTagName的标签，存入*ppElement中
BOOL GetCrntHtmlElement(CWebBrowser2  &ctlBrowser, const CString &strTagName, IHTMLElement **ppElement)
{
    *ppElement = NULL; // initial as NULL
    CString strText;
    CComBSTR cbsText, cbsTagName;
    CComPtr<IHTMLTxtRange> spTxtRange = NULL;

    static CString SELECTTION_TYPE_TEXT = _T("text");
    static CString SELECTTION_TYPE_CONTROL = _T("control");
    static CString SELECTTION_TYPE_NONE = _T("none");

    try
    {
        // calculate the first control based on the user selection
        HRESULT hr = E_FAIL;
        CComPtr<IDispatch> spDispDoc = ctlBrowser.get_Document();
        CComPtr<IHTMLDocument2> spHtmlDoc = NULL;
        hr = spDispDoc->QueryInterface(IID_IHTMLDocument2, (void**)&spHtmlDoc);
        if (FAILED(hr) || NULL == spHtmlDoc)
        {
            return FALSE;
        }
        CComPtr<IHTMLSelectionObject> spSelection = NULL;
        hr = spHtmlDoc->get_selection(&spSelection);
        if(SUCCEEDED(hr) && spSelection)
        {
            hr = spSelection->get_type(&cbsText);
            strText = cbsText;
            if (0 == strText.CompareNoCase(SELECTTION_TYPE_TEXT)
                || 0 == strText.CompareNoCase(SELECTTION_TYPE_NONE) )
            {
                CComPtr<IDispatch> spTextRangeDisp = NULL;
                hr = spSelection->createRange(&spTextRangeDisp);
                if(SUCCEEDED(hr) && spTextRangeDisp)
                {
                    hr = spTextRangeDisp->QueryInterface(IID_IHTMLTxtRange, (void**)&spTxtRange);
                    if(SUCCEEDED(hr) && spTxtRange) // get a text range here
                    {                
                        CComPtr<IHTMLElement> spElement=NULL;
                        // get self element first for tag: such as "h6"
                        hr = spTxtRange->QueryInterface(IID_IHTMLElement, (void**)&spElement);
                        if (SUCCEEDED(hr) && spElement)
                        {
                            hr = spElement->get_tagName(&cbsTagName);
                            if (SUCCEEDED(hr) && 0 == strTagName.CompareNoCase(CString(cbsTagName)) )
                            {    // found  tag now
                                return TRUE;
                            }
                        }
                        // loop search in parent for tag: such as "h6"
                        spElement=NULL;
                        CComPtr<IHTMLElement> spParent = NULL;
                        hr  =spTxtRange->parentElement (&spParent);
                        while (SUCCEEDED(hr) && spParent)
                        {
                            hr = spParent->get_tagName(&cbsTagName);
                            if (SUCCEEDED(hr) && 0 == strTagName.CompareNoCase(CString(cbsTagName)) )
                            {    // found tag now
                                return TRUE;
                            }
                            spElement = spParent;
                            spParent = NULL;
                            hr = spElement->get_parentElement(&spParent);
                        }
                    }
                }
            }
        }
    }
    catch(CException* e)
    {
        e->ReportError();
        e->Delete();        
    }

    return FALSE;
}