Download demo project - 34.6 Kb

Introduction

Ever wanted to make a globally working search combo like in Visual C++? Well, here's how to make it work in your CHtmlView. BTW, this code can be used for anything, not just for a search combo!

Search!

The search feature is based on three functions owned by your CHtmlView-derived class:

CMyHtmlView::FindText(CString searchText, long lFlags /* =2 */, BOOL bNNF /* =FALSE (for internal use)*/)
Searches through the document for the specified word/text and highlights the next match.

Parameters:
- searchText -Text to search for (duh!)
- lFlags - Search flags passed to IHTMLTxtRange::fidText. Can be any combination of 2 (search for whole words only) and 4 (match case)
- bNNF - Used internally. If you want to know what this does, look at the code, I don't remember.
CMyHtmlView::FindText2(CString searchText, long lFlags /* =2 */, CString matchStyle, CString searchID)
Searches through the document for the specified word/text and highlights all found occurrences.

Parameters:
- searchText - Text to search for (again, duh!)
- lFlags - Search flags passed to IHTMLTxtRange::findText. Can be any combination of 2 (search for whole words only) and 4 (match case)
- matchStyle - Allows you to customize the way the found text is highlighted in the document. This is a CSS style assigned to the HTML tag. Default: white text on dark blue background.
- searchID - Use this if you want to highlight multiple search results at one time (you could use a different matchStyle for each different searchID. Normally you would leave this to default.
CMyHtmlView::ClearSearchResults(CString searchID /* ="CHtmlView_Search" */)
Un-highlights the search results from FindText2.

Parameters:
- searchID - the searchID you used in FindText2. If you used the default value, do the same here.

And here comes the code for the functions:

void CMyHtmlView::FindText(CString searchText, 
   long lFlags /* =2 */, BOOL bNNF /* =FALSE  (for internal use)*/)
{
    static CString sLastSearch;
    static BSTR lastBookmark = NULL;

    if(sLastSearch != searchText)
        lastBookmark = NULL;
    sLastSearch = searchText;
    

    IHTMLDocument2 *lpHtmlDocument = NULL;
    LPDISPATCH lpDispatch = NULL;
    lpDispatch = GetHtmlDocument();
    ASSERT(lpDispatch);

    lpDispatch->QueryInterface(IID_IHTMLDocument2, 
                                (void**)&lpHtmlDocument);
    ASSERT(lpHtmlDocument);

    lpDispatch->Release();

    IHTMLElement *lpBodyElm;
    IHTMLBodyElement *lpBody;
    IHTMLTxtRange *lpTxtRange;

    lpHtmlDocument->get_body(&lpBodyElm);
    ASSERT(lpBodyElm);
    lpHtmlDocument->Release();
    lpBodyElm->QueryInterface(IID_IHTMLBodyElement,(void**)&lpBody);
    ASSERT(lpBody);
    lpBodyElm->Release();
    lpBody->createTextRange(&lpTxtRange);
    ASSERT(lpTxtRange);
    lpBody->Release();

    CComBSTR search(searchText.GetLength()+1,(LPCTSTR)searchText);
    bool bFound,bTest;
    long t;

    if(lastBookmark!=NULL)
    {
        lpTxtRange->moveToBookmark(lastBookmark,
                               (VARIANT_BOOL*)&bTest);
        if(!bTest)
        {
            lastBookmark=NULL;
            lpTxtRange->moveStart((BSTR)CComBSTR("Textedit"),1,&t);
            lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
        } else
        {
            lpTxtRange->moveStart((BSTR)CComBSTR("Character"),1,&t);
            lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
        }
    } else
    {
        lpTxtRange->moveStart((BSTR)CComBSTR("Textedit"),0,&t);
        lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
    }
    lpTxtRange->findText((BSTR)search,0,
                    lFlags,(VARIANT_BOOL*)&bFound);

    if(!bFound)
    {
        if(lastBookmark==NULL && !bNNF)
        {
            CString message;
            message.Format("Cannot find the string: '%s'",searchText);
            AfxMessageBox(message);
        } else if(lastBookmark!=NULL)
        {
            lastBookmark = NULL;
            FindText(searchText,lFlags,TRUE);
        }
    } else
    {
        if(lpTxtRange->getBookmark(&lastBookmark)!=S_OK)
            lastBookmark=NULL;
        lpTxtRange->select();
        lpTxtRange->scrollIntoView(TRUE);
    }

    lpTxtRange->Release();
}

void CMyHtmlView::FindText2(CString searchText, 
   long lFlags /* =2 */, CString matchStyle, CString searchID)
{
    ClearSearchResults(searchID);

    IHTMLDocument2 *lpHtmlDocument = NULL;
    LPDISPATCH lpDispatch = NULL;
    lpDispatch = GetHtmlDocument();
    ASSERT(lpDispatch);

    lpDispatch->QueryInterface(IID_IHTMLDocument2, 
                               (void**)&lpHtmlDocument);
    ASSERT(lpHtmlDocument);

    lpDispatch->Release();

    IHTMLElement *lpBodyElm;
    IHTMLBodyElement *lpBody;
    IHTMLTxtRange *lpTxtRange;

    lpHtmlDocument->get_body(&lpBodyElm);
    ASSERT(lpBodyElm);
    lpHtmlDocument->Release();
    lpBodyElm->QueryInterface(IID_IHTMLBodyElement,(void**)&lpBody);
    ASSERT(lpBody);
    lpBodyElm->Release();
    lpBody->createTextRange(&lpTxtRange);
    ASSERT(lpTxtRange);
    lpBody->Release();

    CComBSTR html;
    CComBSTR newhtml;
    CComBSTR search(searchText.GetLength()+1,(LPCTSTR)searchText);

    long t;
    bool bFound;
    while(lpTxtRange->findText(search,0,lFlags,
                        (VARIANT_BOOL*)&bFound),bFound)
    {
        newhtml.Empty();
        lpTxtRange->get_htmlText(&html);
        newhtml.Append("<span id='");
        newhtml.Append((LPCTSTR)searchID);
        newhtml.Append("' style='");
        newhtml.Append((LPCTSTR)matchStyle);
        newhtml.Append("'>");
        if(searchText==" ")
            // doesn't work very well, but prevents (some) shit
            newhtml.Append(" ;"); 
        else 
            newhtml.AppendBSTR(html);
        newhtml.Append("</span>");
        lpTxtRange->pasteHTML(newhtml);
                
        lpTxtRange->moveStart((BSTR)CComBSTR("Character"),1,&t);
        lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
    }

    lpTxtRange->Release();
}

void CMyHtmlView::ClearSearchResults(CString searchID)
{
    CComBSTR testid(searchID.GetLength()+1,searchID);
    CComBSTR testtag(5,"SPAN");
    IHTMLDocument2 *lpHtmlDocument = NULL;
    LPDISPATCH lpDispatch = NULL;
    lpDispatch = GetHtmlDocument();
    ASSERT(lpDispatch);

    lpDispatch->QueryInterface(IID_IHTMLDocument2, 
                                (void**)&lpHtmlDocument);
    ASSERT(lpHtmlDocument);
    lpDispatch->Release();

    IHTMLElementCollection *lpAllElements;
    lpHtmlDocument->get_all(&lpAllElements);
    ASSERT(lpAllElements);
    lpHtmlDocument->Release();

    IUnknown *lpUnk;
    IEnumVARIANT *lpNewEnum;
    if (SUCCEEDED(lpAllElements->get__newEnum(&lpUnk)) && lpUnk != NULL)
    {
        lpUnk->QueryInterface(IID_IEnumVARIANT,(void**)&lpNewEnum);
        ASSERT(lpNewEnum);
        VARIANT varElement;
        IHTMLElement *lpElement;

        while (lpNewEnum->Next(1, &varElement, NULL) == S_OK)
        {
            _ASSERTE(varElement.vt == VT_DISPATCH);
            varElement.pdispVal->QueryInterface
                   (IID_IHTMLElement,(void**)&lpElement);
            ASSERT(lpElement);
            if (lpElement)
            {
                CComBSTR id;
                CComBSTR tag;
                lpElement->get_id(&id);
                lpElement->get_tagName(&tag);
                if((id==testid)&&(tag==testtag))
                {
                    BSTR innerText;
                    lpElement->get_innerHTML(&innerText);
                    lpElement->put_outerHTML(innerText);
                }
            }
            VariantClear(&varElement);
        }
    }
}

The definition:

void FindText(CString searchText, long Flags = 2, 
    BOOL bNNF = FALSE /*for internal use*/);
void FindText2(CString searchText, long Flags = 2, 
    CString matchStyle = "color: white; background-color: darkblue", 
    CString searchID = "CHtmlView_Search");
void ClearSearchResults(CString searchID = "CHtmlView_Search");

And the additional files to include to your CHtmlView derived class:

#include <mshtml.h>
#include <atlbase.h>

Usage

Is you want a search that highlights one matching word at a time, use FindText with the text you want to search for as the first parameter, and the other params left to default.
If you want a search that does the same as above, but that also searches for matching text within words, use the same function as above, but with the second parameter set to 2. (Use this one or the above one for standard combo-box search)
If you want a search that scans through the whole document and highlights all found occurrences, call FindText2 with the text you want to search for as the first parameter, and the second parameter used as described above.

That's it.

BTW, if you want to use the "advanced" features of these functions, you should know at least a little CSS.

Where's the combo?

For information on how to implement the combo-box, check the source code of the demo project. If you have questions on how to do this, post them here or mail them to me: devix@devix.cjb.net.

Known bugs

When you search for " " (space) in FindText2, the function replaces all spaces with non-breaking spaces (otherwise they simply disappear). This causes the page to display like sh*t, but it's still better than the spaces disappearing :)

Update

In this latest update, I have added two more functions that allows you to make a search that selects all off the result at the same time. Here are the screenshots of the demo-app:

Single selection search

Select-all search

Credits

COM code inspired by some script on Nic's Javscript Page.

License

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here

About the Author

Marc Richarme

Engineer
Nokia

Denmark

Member

My programming experience started a long time ago in
QBasic (on a 25MHz 486).
I'm now mainly using Java, C++, C, MFC, Perl and PHP, but have used quite a number of other languages as well for various projects.

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IHTMLElement *lpElement not released

chocm

19:02 17 Oct '09

In the void CMyHtmlView::ClearSearchResults(CString searchID)

the pointer lpElement doesn't call Release() method

...
 if (lpElement)
            {
                CComBSTR id;
                CComBSTR tag;
                lpElement->get_id(&id);
                lpElement->get_tagName(&tag);
                if((id==testid)&&(tag==testtag))
                {
                    BSTR innerText;
                    lpElement->get_innerHTML(&innerText);
                    lpElement->put_outerHTML(innerText);
                }
            }
            VariantClear(&varElement);
        }
 
...

Should I add a line lpElement->Release();

forever loop in findText

obayan

13:59 31 Mar '06

To highlight a page is a cause of forever loop in findText and CPU 100%. http://www.kt.rim.or.jp/~kbk/regex/regex.html[^] is one of the pages, and a search key is "perl" to make the loop. It seems to be a bug, because GoogleBar is same, e.g. open the page, input "perl" in the box, push the highlight button, and it hangs up the IE. But nothing tells about it in MSDN. If you have an idea, please advise me to avoid this problem.

Window flickering

Kronuz

14:32 16 Jun '05

How do you stop the flickering while resizing?
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2 bugs!?

beginner23qweqe

11:20 16 May '05

#1
the system gets slower and slower if you are searching for just one character about 200 times in a larger HTML dokument.

#2
it suddenly stops searching and misses the rest of the matching characters
try it with this: search for "120" and you won't find the last ones at the bottom:

------------------------
<html>
<head>
<title>my html</title>
</head>
<body>
<body bgcolor="#FFFFFF" text="#000000">


<table border=0 width=700 cellpadding=0 cellspacing=5>
<caption><tt>test</tt></caption>

<tr>
<td height=100></td>
<td align="left" valign="top" width=600 height=100><tt>
Nr. 0 
xxx: asdfaseeee567dafsd5 
value 1 
ooo: 10 
hhh: xx0 
uuu: 1x0 
hhh: 1x0 
uuu: 120 
aaa: N 
bbb: N 
</tt></td>
</tr>

<tr>
<td align="left" valign="top" width=600 height=100><tt>
Nr. 1 
xxx: 1234568-0 
value 2 
ooo: 10 
hhh: 115 
uuu: 20 
aaa: N 
bbb: N 
</tt></td>
</tr>

<tr>
<td align="left" valign="top" width=600 height=100><tt>
Nr. 2 
xxx: 1234xsf571-3 
value 3 
ooo: 10 
hhh: 120 
uuu: 10 
aaa: N 
bbb: N 
</tt></td>
</tr>

<tr>
<td align="left" valign="top" width=600 height=100><tt>
Nr. 3 
xxx: asd569adddd 
value 4 
ooo: 10 
hhh: 120 
uuu: 10 
aaa: N 
bbb: N 
</tt></td>
</tr>

<tr>
<td align="left" valign="top" width=600 height=100><tt>
Nr. 4 
xxx: dxfdsaf4570eee 
value 5 
ooo: 10 
you won't find this: 120 
uuu: 10 
aaa: N 
bbb: N 
</tt></td>
</tr>

</table>
</body>
</html>
------------------------

I'm just a beginner, so tell me please if I'm wrong! thx

how to do this in c#

dotnetdevotee

1:39 24 Mar '05

as far as i know i cannot use MFC's like CHtml... in C#. So how do i do this in c# ?
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Re: how to do this in c#

Anonymous

21:30 4 Aug '05

got it i hope Use BHOs They r cool
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How to add jscript in IHTMLDocument and to execute it? (GOOD)

a_jordanov

1:16 9 Oct '04

How to add jscript in IHTMLDocument in order to execute it? I found how to add new HTML elements, but when I try in the same to add java script code nothing happen.

For example:

hr = pBodyElem->get_innerHTML(&bodyInnerHTML);
bodyInnerHTML += "<script>function test() { alert('test'); } </script>";
bodyInnerHTML += "<div style=\"position:absolute;visibility:visible;z-index:100;top:50;left:50;height:100;width:100;overflow:hidden;\"><H1>TEST</H1><div/>";
pBodyElem->put_innerHTML(bodyInnerHTML);

What's wrong? I thought also that IHTMLWindow::execScript will help, but I was wrong. It executes only available scripts in document.

Regards, Alexi

Re: How to add jscript in IHTMLDocument and to execute it? (GOOD)

alexiworld

19:35 10 Oct '04

It's OK! IHTMLWindow is used
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Re: How to add jscript in IHTMLDocument and to execute it? (GOOD)

Alexander Fedorov

5:39 9 Apr '08

Did you found the answer to this question? How to execute script after it is entered?
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How to add jscript in IHTMLDocument and to execute it?

a_jordanov

1:11 9 Oct '04

TEST

";
pBodyElem->put_innerHTML(bodyInnerHTML);

What's wrong? I thought also that IHTMLWindow::execScript will help, but I was wrong. It executes only available scripts in document.

Regards, Alexi

Regular Expression

sixcans

16:26 27 Jun '04

Are there any ways to use regular expression as the search words? Since the above code is using MSHTML's find text function, it cannot use the regular expression.
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above code is not working properly

senmah

23:04 31 May '04

Dear Friend

The above code(Search_view) is not working properly when we type 5 to 6 same word earch should have anchor tag(book mark)

ex:
Type

abcd

Then you find the word is abcd -> Result code found 4 or 5 word only. But we have 7 items.

senmah

Re: above code is not working properly

jotterst

6:38 17 Dec '09

I could be completely wrong, but I ran into this same issue where I have a bunch of tables all with the same headers, the search would get stuck and just loop around a couple of them. As far as I can tell the flaw is with the way IHTMLTxtRange handles bookmarks, if there is a bunch of text that looks the same when you call IHTMLTxtRange::moveToBookmark it doesn't always go back to where you last called IHTMLTxtRange::getBookmark from (you can use IHTMLTxtRange::get_text() to see what your search range actually looks like). So in theory the above code should be fine, but it appears that the IHTMLTxtRange code is flawed. To resolve the issue I pulled the bookmarking paradigm out all together and made the IHTMLTxtRange object a local member to my CHTMLView derived class. Obviously there is some extra work to keep track of it and reset it when needed (ie when the search term changes or you've reached the bottom of the page) but it seems to be working fine so far.

release version

includeh10

6:49 13 Apr '04

the code is not working with release version how to figue it out? all programmers here just use debug version? includeh10
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Re: release version

bruno cortona

20:53 8 Jun '04

replace the bool declarations with VARIANT_BOOL.
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query

mailMonty

2:41 3 Mar '04

in a BHO, if the user clicks on any word how can i know which word user clicked on

there is a function elementFromPoint but that will give the whole Element i want the specific text

how does IE know that the stuff under the mouse is Text cause the mouse pointer changes to a carat when the mouse moves over text on a HTML page

C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg

solution

mailMonty

23:05 11 Mar '04

CComPtr<IHTMLTxtRange> spHTMLTxtRange;
m_pHTMLBody->createTextRange(&spHTMLTxtRange);
 
spHTMLTxtRange->collapse(VARIANT_TRUE);
long x,y;
pEvent->get_clientX(&x);
pEvent->get_clientY(&y);
spHTMLTxtRange->moveToPoint(x,y);
spHTMLTxtRange->expand(CComBSTR("word"),&vtBool);

spHTMLTxtRange now contains the text

C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg

How to skip hidden text?

Edwin Evans

8:35 2 Nov '03

Thanks for the example Marc! It works great.

I have one problem though. Sometimes it finds hidden text and you can't see it. For example, open to http://simplythebest.net/info/vbscript3.html and search for "bus". The first time you don't see anything because it finds the hidden text under "Button 1". That page is using Cascading Style Sheets and the text is marked with "display: none". Other pages like microsoft.com also have similar behavior.

How can I make it work like the "Find" dialog that skips this text? Or perhaps popping out the menu would be even better.

Thank you,
Edwin

This with frames

inc99

5:05 5 Oct '03

void CYourHtmlView::FindText(CString searchText, long lFlags /* =2 */, BOOL bNNF /* =FALSE   (for internal use)*/)
{
     static CString sLastSearch;
     static BSTR lastBookmark = NULL;

     BOOL bFound = FALSE;
     BOOL bTest = FALSE;

     if(sLastSearch != searchText)
          lastBookmark = NULL;
     sLastSearch = searchText;


     IHTMLDocument2 *lpHtmlDocument = NULL;
     LPDISPATCH lpDispatch = NULL;
     lpDispatch = GetHtmlDocument();
     ASSERT(lpDispatch);

     lpDispatch->QueryInterface(IID_IHTMLDocument2, (void**)&lpHtmlDocument);
     ASSERT(lpHtmlDocument);

     lpDispatch->Release();

     IHTMLElement *lpBodyElm;
     IHTMLBodyElement *lpBody;
     IHTMLTxtRange *lpTxtRange;

     lpHtmlDocument->get_body(&lpBodyElm);
     ASSERT(lpBodyElm);

     lpBodyElm->QueryInterface(IID_IHTMLBodyElement,(void**)&lpBody);


     if(!lpBody)
     {
            // Frame support added by inc99
          long FrameCount; // (local) number of frames

          IHTMLFramesCollection2 *lpFramesCol;
          lpHtmlDocument->get_frames(&lpFramesCol);

          lpFramesCol->get_length(&FrameCount);

          if(bNNF)     // if TRUE last search object in the frame is found
          {
               m_Frames++;     // !!! the class variable
          }

          if(m_Frames == FrameCount)
          {
               m_Frames = 0;
          }

            VARIANT vFrame;
            VARIANT ret;
            vFrame.vt = VT_UINT;
          vFrame.lVal = m_Frames;     //     vFrame.lVal gets the value of the class variable
                                        //     so the right frame is called.

          if (SUCCEEDED (lpFramesCol->item(&vFrame, &ret)) ) // U see
          {
                  IHTMLWindow2 *pWindow = NULL;
                  if(SUCCEEDED(ret.pdispVal->QueryInterface(IID_IHTMLWindow2, (LPVOID*)&pWindow)))
               {
                    IHTMLDocument2 *MylpHtmlDocument = NULL;
                    IHTMLElement *MylpBodyElm = NULL;
                    if(SUCCEEDED(pWindow->get_document(&MylpHtmlDocument)))
                    {
                         MylpHtmlDocument->get_body(&MylpBodyElm);
                         ASSERT(MylpBodyElm);
                         MylpHtmlDocument->Release();
                         MylpBodyElm->QueryInterface(IID_IHTMLBodyElement, (void**)&lpBody);
                    }
                    MylpBodyElm->Release();
               }
               pWindow->Release();
          }
     }

     // Now lpBody points to the body of the correct frame and the searching can begin

     lpHtmlDocument->Release();

     ASSERT(lpBody);
     lpBodyElm->Release();
     lpBody->createTextRange(&lpTxtRange);
     ASSERT(lpTxtRange);
     lpBody->Release();

     CComBSTR search(searchText.GetLength()+1,(LPCTSTR)searchText);
     long t;

     if(lastBookmark!=NULL)
     {
          lpTxtRange->moveToBookmark(lastBookmark,(VARIANT_BOOL*)&bTest);
          if(!bTest)
          {
               lastBookmark=NULL;
               lpTxtRange->moveStart((BSTR)CComBSTR("Textedit"),1,&t);
               lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
          } else
          {
               lpTxtRange->moveStart((BSTR)CComBSTR("Character"),1,&t);
               lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
          }
     } else
     {
          lpTxtRange->moveStart((BSTR)CComBSTR("Textedit"),0,&t);
          lpTxtRange->moveEnd((BSTR)CComBSTR("Textedit"),1,&t);
     }
     lpTxtRange->findText((BSTR)search,0,lFlags,(VARIANT_BOOL*)&bFound);

     if(!bFound)
     {
          if(lastBookmark==NULL && !bNNF)
          {
               CString message;
               message.Format("Tekst niet gevonden: '%s'\n\nOf pagina is niet actief (klik op pagina en zoek opnieuw)",searchText);
               AfxMessageBox(message);
          } else if(lastBookmark!=NULL)
          {
               lastBookmark = NULL;
               FindText(searchText,lFlags,TRUE);
          }
     } else
     {
          if(lpTxtRange->getBookmark(&lastBookmark)!=S_OK)
               lastBookmark=NULL;
          lpTxtRange->select();
          lpTxtRange->scrollIntoView(TRUE);
     }

     lpTxtRange->Release();

}

Highlight the search parameter with some extra words

pallavibondre

7:54 1 Oct '03

Hi,
this is really good example of searching a word inside HTMLView.

onw more thing i want to go is... my html code has text like
[Parameter1].... some text.... [Parameter2].... [label] and so one...

I am searching '[' to get the parameters list from html code. but i want to highlight full word (eq- [Parameter1] )... words inside [ ] are generating at run time...

can you help me for this?

thank you
Pallavi

The "right" way to do it.

Shomoiog

3:37 30 Jul '03

How about using IMarkupServices / IMarkupContainer / IMarkupPointer? That seems to be the "right way" of doing it, not by altering the html content
Sign In·View Thread·Permalink	2.00/5 (1 vote)

Re: The "right" way to do it.

Neville Franks

11:48 11 Aug '03

Shomoiog wrote: How about using IMarkupServices / IMarkupContainer / IMarkupPointer? That seems to be the "right way" of doing it, not by altering the html content How about a nice article showing us how to do this. Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com
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Re: The "right" way to do it.

Yu Hailiang

18:03 11 Apr '04



void highLight(IHTMLDocumentPtr doc, const CString& highlightText, bool bHighLight, const CString& highlightAttr)

{

	CComQIPtr<IMarkupServices> pMS;

	CComQIPtr<IMarkupContainer> pMC;

	CComPtr<IMarkupPointer> ptrBegin, ptrEnd;

 

	_bstr_t attr(highlightAttr);

	_bstr_t textToFind(highlightText);

	

	pMS = doc;

	pMC = doc;

	if(pMS && pMC)

	{

		pMS->CreateMarkupPointer(&ptrBegin);

		pMS->CreateMarkupPointer(&ptrEnd);

		

		ptrBegin->SetGravity(POINTER_GRAVITY_Right);

		ptrEnd->SetGravity(POINTER_GRAVITY_Left);

		

		ptrBegin->MoveToContainer(pMC, TRUE);

		ptrEnd->MoveToContainer(pMC, FALSE);

		

		while(TRUE)

		{   // Find text

			HRESULT hr = ptrBegin->FindText(textToFind, 0, ptrEnd, NULL);

			

			if (S_FALSE == hr)  break;// did not find the text

            

			IHTMLElementPtr pFontEl;

			if (bHighLight)

			{

				hr = pMS->CreateElement(TAGID_FONT, attr, &pFontEl); // create FONT element with attributes for selection

				hr = pMS->InsertElement( pFontEl, ptrBegin, ptrEnd);     // Insert created element to context

				ptrBegin->MoveToPointer(ptrEnd);                         // Continue searching

			}

			else

			{

				// Remove last created element in the context                                                       

				hr = ptrBegin->CurrentScope( &pFontEl);

				hr = pMS->RemoveElement(pFontEl);

				ptrBegin->MoveToPointer(ptrEnd);                    // Continue searching   

			}

		}

	}

}

for example:



highLight(pHTMLDoc, _T("google"), true, _T("COLOR=#0000ff STYLE=\"background-color:#ffff00\""));

Re: The "right" way to do it.

James R. Twine

10:05 23 Aug '04

A very nice example of modifying the document contents in-place! But I offer the following: IMHO, one should avoid any unnecessary creation of objects, as they just waste time and provide no benefit.

The line:

     void highLight(IHTMLDocumentPtr doc, const CString& highlightText, bool bHighLight, const CString& highlightAttr)

   -At worst case forces the caller to incur the creation of two CString objects, each with its own overhead, when they are not really required. Simply changing the method to take LPCTSTR will work better (perhaps), because it does not require the caller to create a pair of CString objects. If the caller already has CStrings available, they will still work correctly with this change.

   Not everyone agrees with me on things like this, but I offer them, anyway -- take 'em or leave 'em!

   And would you like a reference to go with that first parameter? Smile | :)

Just a thought...

Peace!

-=- James
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Re: The "right" way to do it.

peterchen

2:49 27 Jul '10

I generally agree with that, however, I've noticed that this leads sometimes to rather awkward interfaces - e.g.

void foo(LPCTSTR a, CString const & b)

...because for b you internally use CString functionality (and don't want to force construction of a CString if the caller already has one).
That's kind of the implementaiton leaking into that itnerface, which sounds ugly.

In that case I usually use CString for both. What do you think?

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