Click here to Skip to main content
Click here to Skip to main content
Add your own
alternative version

Capture an HTML document as an image

, , 19 May 2004
Capturing HTML documents as images
/*
 *	$Header: $
 *
 *	$History: $
 */
#include "stdafx.h"
#include <exdispid.h>
#include "CreateHTMLImage.h"
#include "FileSpec.h"
#include "BitmapDC.h"

IMPLEMENT_DYNCREATE(CCreateHTMLImage, CWnd)

BEGIN_EVENTSINK_MAP(CCreateHTMLImage, CWnd)
	ON_EVENT(CHtmlView, CHILDBROWSER, DISPID_DOCUMENTCOMPLETE, DocumentComplete, VTS_DISPATCH VTS_PVARIANT)
END_EVENTSINK_MAP()

LPCTSTR CCreateHTMLImage::m_ImageFormats[] =
{
	"image/bmp",
	"image/jpeg",
	"image/gif",
	"image/tiff",
	"image/png"
};

// CCreateHTMLImage
CCreateHTMLImage::CCreateHTMLImage() : CWnd()
{
	SetSaveImageFormat(eJPG);
}

CCreateHTMLImage::~CCreateHTMLImage()
{
}

BOOL CCreateHTMLImage::SetSaveImageFormat(eOutputImageFormat format)
{
	USES_CONVERSION;
	ASSERT(format >= 0 && format < eImgSize);

	return GetEncoderClsid(A2W(m_ImageFormats[format]), &m_encoderClsid) != -1;
}

BOOL CCreateHTMLImage::CreateControlSite(COleControlContainer* pContainer,  COleControlSite** ppSite, UINT /* nID */, REFCLSID /* clsid */)
{
	ASSERT(ppSite != NULL);
	*ppSite = new CHTMLImageControlSite(pContainer);
	return TRUE;
}

// CCreateHTMLImage member functions
BOOL CCreateHTMLImage::Create(CWnd *pParent)
{
	ASSERT(GetSafeHwnd() == HWND(NULL));
	ASSERT(pParent);
	ASSERT_KINDOF(CWnd, pParent);
	ASSERT(IsWindow(pParent->GetSafeHwnd()));

	CRect rect;

	if (!CWnd::Create(NULL, NULL, WS_CHILD, rect, pParent, 0, NULL))
		return FALSE;

	//	Window style must include WS_VISIBLE even though we never see the window. Otherwise the WebBrowser
	//	seems not to load documents.
	if (!m_pBrowserWnd.CreateControl(CLSID_WebBrowser, _T(""), WS_VISIBLE | WS_CHILD, rect, this, CHILDBROWSER))
	{
		DestroyWindow();
		return FALSE;
	}

	// cache the dispinterface
	LPUNKNOWN lpUnk = m_pBrowserWnd.GetControlUnknown();
	HRESULT hr = lpUnk->QueryInterface(IID_IWebBrowser2, (void**) &m_pBrowser);

	if (!SUCCEEDED(hr))
	{
		m_pBrowser = NULL;
		m_pBrowserWnd.DestroyWindow();
		DestroyWindow();
		return FALSE;
	}

	return TRUE;
}

BOOL CCreateHTMLImage::CreateImage(LPCTSTR szSrcFilename, LPCTSTR szDestFilename, CSize srcSize, CSize outputSize)
{
	ASSERT(GetSafeHwnd());
	ASSERT(IsWindow(GetSafeHwnd()));
	ASSERT(szSrcFilename);
	ASSERT(AfxIsValidString(szSrcFilename));
	ASSERT(szDestFilename);
	ASSERT(AfxIsValidString(szDestFilename));

	CRect rect(CPoint(0, 0), srcSize);

	//	The WebBrowswer window size must be set to our srcSize
	//	else it won't render everything
	MoveWindow(&rect);
	m_pBrowserWnd.MoveWindow(&rect);

	COleVariant	  vUrl(szSrcFilename, VT_BSTR),
				  vFlags(long(navNoHistory | navNoReadFromCache | navNoWriteToCache), VT_I4),
				  vNull(LPCTSTR(NULL), VT_BSTR);
	COleSafeArray vPostData;

	if (m_pBrowser->Navigate2(&vUrl, &vFlags, &vNull, &vPostData, &vNull) == S_OK)
		//	We have to pump messages to ensure the event handler (DocumentComplete)
		//	is called.
		RunModalLoop();
	else
		return FALSE;

	//	We only get here when DocumentComplete has been called, which calls EndModalLoop
	//	and causes RunModalLoop to exit.
	IDispatch *pDoc = (IDispatch *) NULL;
	HRESULT	  hr = m_pBrowser->get_Document(&pDoc);

	if (FAILED(hr))
		return FALSE;

	return CreateImage((IHTMLDocument2 *) pDoc, szDestFilename, srcSize, outputSize);
}

BOOL CCreateHTMLImage::CreateImage(IHTMLDocument2 *pDoc, LPCTSTR szDestFilename, CSize srcSize, CSize outputSize)
{
	USES_CONVERSION;
	ASSERT(szDestFilename);
	ASSERT(AfxIsValidString(szDestFilename));
	ASSERT(pDoc);

	//	Get our interfaces before we create anything else
	IHTMLElement	   *pElement = (IHTMLElement *) NULL;
	IHTMLElementRender *pRender = (IHTMLElementRender *) NULL;

	//	Let's be paranoid...
	if (pDoc == (IHTMLDocument2 *) NULL)
		return FALSE;

	pDoc->get_body(&pElement);

	if (pElement == (IHTMLElement *) NULL)
		return FALSE;

	pElement->QueryInterface(IID_IHTMLElementRender, (void **) &pRender);

	if (pRender == (IHTMLElementRender *) NULL)
		return FALSE;

	CFileSpec fsDest(szDestFilename);
	CBitmapDC destDC(srcSize.cx, srcSize.cy);

	pRender->DrawToDC(destDC);

	CBitmap *pBM = destDC.Close();
	
	Bitmap *gdiBMP = Bitmap::FromHBITMAP(HBITMAP(pBM->GetSafeHandle()), NULL);
	Image  *gdiThumb = gdiBMP->GetThumbnailImage(outputSize.cx, outputSize.cy);

	gdiThumb->Save(A2W(fsDest.GetFullSpec()), &m_encoderClsid);
	delete gdiBMP;
	delete gdiThumb;
	delete pBM;
	return TRUE;
}

void CCreateHTMLImage::DocumentComplete(LPDISPATCH pDisp, VARIANT* URL)
{
	UNUSED_ALWAYS(pDisp);
	UNUSED_ALWAYS(URL);
	TRACE("CCreateHTMLImage::DocumentComplete\n");
	EndModalLoop(0);
}

int CCreateHTMLImage::GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
{
	UINT  num = 0;          // number of image encoders
	UINT  size = 0;         // size of the image encoder array in bytes

	ImageCodecInfo* pImageCodecInfo = NULL;
	GetImageEncodersSize(&num, &size);

	if(size == 0)
		return -1;  // Failure

	pImageCodecInfo = (ImageCodecInfo*)(malloc(size));

	if(pImageCodecInfo == NULL)
		return -1;  // Failure

	GetImageEncoders(num, size, pImageCodecInfo);

	for(UINT j = 0; j < num; ++j)
	{
		if (wcscmp(pImageCodecInfo[j].MimeType, format) == 0)
		{
			*pClsid = pImageCodecInfo[j].Clsid;
			free(pImageCodecInfo);
			return j;  // Success
		}    
	}

	free(pImageCodecInfo);
	return -1;  // Failure
}

//////////////////////////////////////////////////////////////////////
//	Implementation of the CHTMLImageControlSite class, including the
//	IDocHostUIHandler implementation
BEGIN_INTERFACE_MAP(CHTMLImageControlSite, COleControlSite)
	INTERFACE_PART(CHTMLImageControlSite, IID_IDocHostUIHandler, DocHostUIHandler)
END_INTERFACE_MAP()

CHTMLImageControlSite::CHTMLImageControlSite(COleControlContainer* pContainer) : COleControlSite(pContainer)
{
}

// IUnknown methods
STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::QueryInterface(REFIID riid, void **ppvObj)
{
	METHOD_PROLOGUE_EX_(CHTMLImageControlSite, DocHostUIHandler)
	return pThis->ExternalQueryInterface(&riid, ppvObj);
}

STDMETHODIMP_(ULONG) CHTMLImageControlSite::XDocHostUIHandler::AddRef()
{
	METHOD_PROLOGUE_EX_(CHTMLImageControlSite, DocHostUIHandler)
	return pThis->ExternalAddRef();
}

STDMETHODIMP_(ULONG) CHTMLImageControlSite::XDocHostUIHandler::Release()
{
	METHOD_PROLOGUE_EX_(CHTMLImageControlSite, DocHostUIHandler)
	return pThis->ExternalRelease();
}

// IDocHostUIHandler methods
STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::ShowContextMenu(DWORD /*dwID*/, POINT * /*ppt*/, IUnknown * /*pcmdtReserved*/, IDispatch * /*pdispReserved*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::GetHostInfo(DOCHOSTUIINFO *pInfo)
{
	pInfo->dwFlags = DOCHOSTUIFLAG_NO3DBORDER | DOCHOSTUIFLAG_SCROLL_NO;
	return S_OK;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::ShowUI(DWORD /*dwID*/, IOleInPlaceActiveObject * /*pActiveObject*/, IOleCommandTarget * /*pCommandTarget*/, IOleInPlaceFrame * /*pFrame*/, IOleInPlaceUIWindow * /*pDoc*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::HideUI(void)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::UpdateUI(void)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::EnableModeless(BOOL /*fEnable*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::OnDocWindowActivate(BOOL /*fActivate*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::OnFrameWindowActivate(BOOL /*fActivate*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::ResizeBorder(LPCRECT /*prcBorder*/, IOleInPlaceUIWindow * /*pUIWindow*/, BOOL /*fRameWindow*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::TranslateAccelerator(LPMSG /*lpMsg*/, const GUID * /*pguidCmdGroup*/, DWORD /*nCmdID*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::GetOptionKeyPath(LPOLESTR * /*pchKey*/, DWORD /*dw*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::GetDropTarget(IDropTarget * /*pDropTarget*/, IDropTarget ** /*ppDropTarget*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::GetExternal(IDispatch ** /*ppDispatch*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::TranslateUrl(DWORD /*dwTranslate*/, OLECHAR * /*pchURLIn*/, OLECHAR ** /*ppchURLOut*/)
{
	return S_FALSE;
}

STDMETHODIMP CHTMLImageControlSite::XDocHostUIHandler::FilterDataObject(IDataObject * /*pDO*/, IDataObject ** /*ppDORet*/)
{
	return S_FALSE;
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Share

About the Authors

Rob Manderson

United States United States
I've been programming for 35 years - started in machine language on the National Semiconductor SC/MP chip, moved via the 8080 to the Z80 - graduated through HP Rocky Mountain Basic and HPL - then to C and C++ and now C#.
 
I used (30 or so years ago when I worked for Hewlett Packard) to repair HP Oscilloscopes and Spectrum Analysers - for a while there I was the one repairing DC to daylight SpecAns in the Asia Pacific area.
 
Afterward I was the fourth team member added to the Australia Post EPOS project at Unisys Australia. We grew to become an A$400 million project. I wrote a few device drivers for the project under Microsoft OS/2 v 1.3 - did hardware qualification and was part of the rollout team dealing directly with the customer.
 
Born and bred in Melbourne Australia, now living in Scottsdale Arizona USA, became a US Citizen on September 29th, 2006.
 
I work for a medical insurance broker, learning how to create ASP.NET websites in VB.Net and C#. It's all good.
 
Oh, I'm also a Kentucky Colonel. http://www.kycolonels.org

Vadim Tabakman
Web Developer
United States United States
C/C++ Programmer. OS of choice is any Win32 OS. Started working in the gaming industry, programming mainframe VOS OS and dealing with Slot machine serials comms protocols, creating test-tools and line monitoring software on W2K.
 
Moved on to working in a small software company that worked with electronic forms. Glad I spent most of my time there learning new technologies and increasing my programming skills. I wasn't going to learning anything from anyone there. Well, except the odd one person who is now a CPian.
 
Now working in a company that works with Security, Identity and Trust Solutions. Learning lots about encryption, signing, digital signatures, hashing and all sorts of new buzz words. It might as well be another language.

| Advertise | Privacy | Mobile
Web01 | 2.8.140827.1 | Last Updated 20 May 2004
Article Copyright 2004 by Rob Manderson, Vadim Tabakman
Everything else Copyright © CodeProject, 1999-2014
Terms of Service
Layout: fixed | fluid