Adding a hyperlink to a RichEdit

[cyprus106]

I can add URL autodetection functionality to a RichEdit easily, but I want to be able to add a hyperlink, (i.e. when the user clicks on something that says:
Go to tek tips
then it will go to the url

http://www.tek-tips.com

How would I go about setting this up?
I've spent the entire day trying and guessing (and failing...) I hope somebody on here has a better idea.
Thanks, Cyprus

 

[Doezel]

Hello,

have you solved this riddle already? I want to do the same...

 

[butthead]

a url is a hyperlink, so expanding upon your url detection
should bejust adding to the code.

when user clicks on this ***
and the string equals this ***
do this ***

tomcruz.net

 

[cyprus106]

Here's my code... I actually grabbed the code from my very basic test project. I've elaborated on it since then, if I remember right, so if something doesn't work let me know and I'll dig into the code I added on to it, because I seem to recall a few small bugs that I worked out of this at one point. When I pulled this back out, I only fired it up, I didn't even click the link but I know it works. I think one of the problems I worked out once was that you couldn't erase the link after you'd put it in. It wouldn't let you backspace it out because it was "protected". I may be remembering wrong, it was a while ago, but this should help. Like i said, if you've got any problems, let me know.


The form has a richedit and a button. That's it.

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
        ::SendMessage (rich->Handle, EM_SETEVENTMASK, 0 , ENM_LINK|ENM_PROTECTED);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::OnNotify(TMessage &Message)
{
       NMHDR *pNMHDR;
       pNMHDR = (NMHDR *)Message.LParam;

       switch (pNMHDR->code)
       {
               case EN_LINK :
                       OnLink (pNMHDR, (LRESULT *)&Message.Result);
                       break;

               case EN_PROTECTED :
                       OnProtected (pNMHDR, (LRESULT *)&Message.Result);
                       break;

               default :
                       TForm::Dispatch(&Message);
       }
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
        DWORD dwStart;

        //get insert position
        if (::SendMessage (rich->Handle, EM_GETSEL, (WPARAM)&dwStart, NULL) == -1)
                return;

	InsertLink (rich->Handle, dwStart, "Go to Tek-Tips", "[URL unfurl="true"]www.tek-tips.com");[/URL]
}
//---------------------------------------------------------------------------
bool __fastcall TForm1::InsertLink(HWND hRich, int nPos, const char *pszTitle, const char *pszURL)
{
	Richedit::CHARFORMAT2 cf2;;
	int nTitleLen, nURLen;
	char *pszLinkBuf = NULL;

        //check if ptrs are valid and pszTitle has 2 chars at least
	if (!pszURL || !pszTitle || !pszTitle[0] || !pszTitle[1])
		return FALSE; //title too short

        //get lengths of title & URL
	nTitleLen = strlen (pszTitle);
	nURLen = strlen (pszURL) + URL_HDR_LEN;

        //alloc suff. buf for sprintf, you can manage it some other way;
        //to have constant buf, or use EM_SETSEL&EM_REPLACESEL inserting
        //text piece by piece to avoid new/delete for each link
        pszLinkBuf = new char [nTitleLen + nURLen];
        if (!pszLinkBuf)
                return FALSE; //alloc failed

        //reset cf2
        memset (&cf2, 0, sizeof(cf2));
	cf2.cbSize = sizeof(cf2);

	//1st letter+url len+url text+rest of the title
	// "G[0018www.experts-exchange.com]o to Experts-Exchange"
	sprintf (pszLinkBuf, "%c%04X%s%s", *pszTitle, nURLen, pszURL, pszTitle + 1);

	//set title text
	::SendMessage (hRich, EM_SETSEL, nPos, nPos);
	::SendMessage (hRich, EM_REPLACESEL, 0, (LPARAM)pszLinkBuf);

        //now we don't need the buf anymore, so delete it
        delete[] pszLinkBuf;
	
	//apply link style on'G' 
	::SendMessage (hRich, EM_SETSEL, nPos, nPos+1);
	cf2.dwMask = CFE_LINK|CFE_PROTECTED;
	cf2.dwEffects = CFM_LINK|CFM_PROTECTED;
	::SendMessage (hRich, EM_SETCHARFORMAT, SCF_SELECTION , (LPARAM)&cf2);

	//hide URL text
	nPos++;
	
	::SendMessage (hRich, EM_SETSEL, nPos, nPos+nURLen);
	cf2.dwMask = CFE_LINK|CFE_PROTECTED|CFE_HIDDEN;
	cf2.dwEffects = CFM_LINK|CFM_PROTECTED|CFM_HIDDEN;
	::SendMessage (hRich, EM_SETCHARFORMAT, SCF_SELECTION , (LPARAM)&cf2);

	//apply link&protected style on the rest of the title
	nPos += nURLen;

	::SendMessage (hRich, EM_SETSEL, nPos, nPos+nTitleLen-1);
	cf2.dwMask = CFE_LINK|CFE_PROTECTED;
	cf2.dwEffects = CFM_LINK|CFM_PROTECTED;
	::SendMessage (hRich, EM_SETCHARFORMAT, SCF_SELECTION , (LPARAM)&cf2);

	return TRUE;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::OnLink(NMHDR* pNMHDR, LRESULT* pResult)
{
	ENLINK *pEnLink = (ENLINK *)pNMHDR;

	if (pEnLink->msg == WM_LBUTTONDOWN)
	{
		Richedit::TEXTRANGE tr;
		int nURLen, nRange;

                //prepare TEXTRANGE and aloc suff. buf for clicked link text
		tr.chrg = pEnLink->chrg;
		tr.lpstrText = new TCHAR[tr.chrg.cpMax-tr.chrg.cpMin + 1];

		if (!tr.lpstrText)
			return; //alloc failed

		//get the link text
		nRange = ::SendMessage (rich->Handle, EM_GETTEXTRANGE, 0 , (LPARAM)&tr);

		//get URL length
		if (!sscanf (tr.lpstrText + 1, "%04X", &nURLen) ||
			nRange < nURLen + 1)
			return;

		//place zero at the URL's end
		tr.lpstrText[nURLen + 1] = 0;

		//here is your URL
		ShellExecute (NULL, "open", (tr.lpstrText + 1 + URL_HDR_LEN), NULL, NULL, SW_SHOW);

		delete[] tr.lpstrText;
	}
	
	*pResult = 0;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::OnProtected(NMHDR* pNMHDR, LRESULT* pResult)
{
	ENPROTECTED *pEnProtected = (ENPROTECTED *)pNMHDR;

        //return 0 to allow modification, 1 otherwise
	//allow copy, but deny link modification
	*pResult = pEnProtected->msg != WM_COPY;
}

And the header...

#include <stdio.h>

#define URL_BUF_LEN 512
#define URL_HDR_LEN 4
//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published:	// IDE-managed Components
        TRichEdit *rich;
        TButton *Button1;
        void __fastcall Button1Click(TObject *Sender);
private:	// User declarations
        void __fastcall OnLink(NMHDR* pNMHDR, LRESULT* pResult);
        void __fastcall OnProtected(NMHDR* pNMHDR, LRESULT* pResult);
public:		// User declarations
        __fastcall TForm1(TComponent* Owner);
        bool __fastcall InsertLink(HWND hRich, int nPos, const char *pszTitle, const char *pszURL);

protected:
        void __fastcall OnNotify(TMessage &Message);

        BEGIN_MESSAGE_MAP
        MESSAGE_HANDLER(WM_NOTIFY, TMessage, OnNotify)
        END_MESSAGE_MAP(TForm)

};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
#endif

Cyprus

 

[cyprus106]

ok, for my life I have no idea what the problem is. And maybe somebody can check the code and tell me. I copied and pasted my slightly modified code into one of my new projects, and the URL code didn't work! So I copied and pasted the code letter-for-letter from my example program that I've posted before, and ran both programs. The example URL worked like a charm and my URL didn't work at all. Then I tried just creating a brand new project and doing the exac tsame thing as the example and it STILL doesn't work! Anyone know the problem? The ONLY thing I could think of was that there was some discrepency between BCB5 and BCB6?

I'll probably post this in it's own thread pretty soon here...

Cyprus