How can I create href links on CHtmlEditCtrl?

Question

I make a dialog using visual studio 2017 c++ MFC, and web links by CHtmlEditCtrl.

But, the href links not working...

I expect the following behavior.

clicking the link
the browser (ex. chrome) start
displaying the web page on the browser

How can I fix my code?

BOOL CTestDlg::OnInitDialog()
{
    CDialogEx::OnInitDialog();
    // ...

    CHtmlEditCtrl* htmledit = new CHtmlEditCtrl();
    CEdit* edit = (CEdit*)GetDlgItem(IDC_EDIT_HTML);
    CRect rc;
    edit->GetWindowRect(&rc);
    this->ScreenToClient(&rc);
    htmledit->Create(0, (WS_CHILD | WS_VISIBLE), rc, this, IDC_EDIT_HTML, 0);

    CComPtr<IHTMLDocument2> document;
    htmledit->GetDocument(&document);
    WaitForComplete(document);
    htmledit->SetDocumentHTML(_T("<a href=\"https://www.google.co.jp/\" target=\"_blank\">Google</a><br><a href=\"https://stackoverflow.com/\" target=\"_blank\">stackoverflow</a>"));
    WaitForComplete(document);

    return TRUE;
}

void CTestDlg::WaitForComplete(IHTMLDocument2* document)
{
    BSTR ready;
    document->get_readyState(&ready);
    while (wcscmp(ready, L"complete"))
    {
        AfxPumpMessage();
        document->get_readyState(&ready);
    };
}

I referred to the following site.

Barmak Shemirani Barmak Shemirani · Accepted Answer · 2019-02-02T17:07:29

CHtmlEditCtrl overrides NavigateComplete2 and calls SetDesignMode(TRUE). If you want a viewer, instead of editor, then override as follows:

class CMyHtmlEditCtrl : public CHtmlEditCtrl
{
    virtual void _OnNavigateComplete2(LPDISPATCH, VARIANT FAR*) 
    { 
        //SetDesignMode(TRUE);
    }
public:
    DECLARE_EVENTSINK_MAP()
};

BEGIN_EVENTSINK_MAP(CMyHtmlEditCtrl, CHtmlEditCtrl)
    ON_EVENT_REFLECT(CMyHtmlEditCtrl, 252 /* NavigateComplete2 */, _OnNavigateComplete2, VTS_DISPATCH VTS_PVARIANT)
END_EVENTSINK_MAP()

Use this class instead of CHtmlEditCtrl. You won't need WaitForComplete anymore because SetDesignMode is not blocking the calls in OnInitDialog.

_OnBeforeNavigate

In addition, add # to the link: href="#http://www.google.com" so that the browser control doesn't know what to do with the link, and lets you handle it instead. You then convert #http://www.google.com to http://www.google.com and open the link.

Declare as CMyHtmlEditCtrl browser; as class member to avoid leaks.

Example:

class CMyHtmlEditCtrl : public CHtmlEditCtrl
{
public:
    virtual void _OnNavigateComplete2(LPDISPATCH, VARIANT FAR*)
    {
        //SetDesignMode(TRUE);
    }

    void _OnBeforeNavigate2(LPDISPATCH,
        VARIANT* URL, VARIANT*, VARIANT*, VARIANT*, VARIANT*, VARIANT_BOOL*)
    {
        CString str(V_BSTR(URL));
        int pos = str.Find(L'#');
        if(pos >= 0)
        {
            str = str.Mid(pos + 1);
            ShellExecute(NULL, L"open", str, NULL, NULL, SW_SHOWNORMAL);
        }
    }

    DECLARE_EVENTSINK_MAP()
};

BEGIN_EVENTSINK_MAP(CMyHtmlEditCtrl, CHtmlEditCtrl)
    ON_EVENT_REFLECT(CMyHtmlEditCtrl, 250, _OnBeforeNavigate2, VTS_DISPATCH VTS_PVARIANT VTS_PVARIANT VTS_PVARIANT VTS_PVARIANT VTS_PVARIANT VTS_PBOOL)
    ON_EVENT_REFLECT(CMyHtmlEditCtrl, 252, _OnNavigateComplete2, VTS_DISPATCH VTS_PVARIANT)
END_EVENTSINK_MAP()

...
//declare class member for CMyDialog:
CMyHtmlEditCtrl browser;
...

CMyHtmlEditCtrl browser;
BOOL CMyDialog::OnInitDialog()
{
    CDialogEx::OnInitDialog();

    CWnd* edit = GetDlgItem(IDC_EDIT1);
    CRect rc;
    edit->GetWindowRect(&rc);
    ScreenToClient(&rc);
    browser.Create(0, WS_CHILD | WS_VISIBLE, rc, this, 301, 0);

    CString html = LR"(<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 
Transitional//EN">
<html>
<head>
<style type="text/css">
body
{
    border:1px solid gray;
}
</style>
</head>
<body>
<a href="#http://www.stackoverflow.com">http://www.stackoverflow.com</a>
</body>
</html>
)";

    browser.SetDocumentHTML(html);
    return TRUE;
}

How can I create href links on CHtmlEditCtrl?

1 Answers