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URLEncode

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25 Jun 2001 172.3K   1.4K   21   23
Convert string using URLEncode method

URLEncode

I use this functions to prepare POST strings with XML data. The first function URLEncode1 uses less memory but is slower than the second URLEncode2. Both functions return a CString and get a CString as the input parameter.

The demo project contains sample usage with execution time of presented functions.

Source

Helper function

inline BYTE toHex(const BYTE &x)
{
	return x > 9 ? x + 55: x + 48;
}

URLEncode1

CString URLEncode1(CString sIn)
{
    CString sOut;
	
    int k;
    const int nLen = sIn.GetLength() + 1;

    register LPBYTE pOutTmp = NULL;
    LPBYTE pOutBuf = NULL;
    register LPBYTE pInTmp = NULL;
    LPBYTE pInBuf =(LPBYTE)sIn.GetBuffer(nLen);
    BYTE b = 0;

    //count not alphanumeric characters
    k = 0;
	
    pInTmp = pInBuf;
    while(*pInTmp)
    {
        if (!isalnum(*pInTmp) && !isalnum(*pInTmp))
            k++;
        pInTmp++;
    }

    //alloc out buffer
    pOutBuf = (LPBYTE)sOut.GetBuffer(nLen  + 2 * k); //new BYTE [nLen  + 3 * k];

    if(pOutBuf)
    {
        pInTmp	= pInBuf;
	pOutTmp = pOutBuf;
		
	// do encoding
	while (*pInTmp)
        {
	    if(isalnum(*pInTmp))
                *pOutTmp++ = *pInTmp;
	    else
		if(isspace(*pInTmp))
		    *pOutTmp++ = '+';
		else
		{
		    *pOutTmp++ = '%';
		    *pOutTmp++ = toHex(*pInTmp>>4);
		     *pOutTmp++ = toHex(*pInTmp%16);
		}
	    pInTmp++;
	}
	
	*pOutTmp = '\0';
	//sOut=pOutBuf;
	//delete [] pOutBuf;
	sOut.ReleaseBuffer();
    }
    sIn.ReleaseBuffer();
    return sOut;
}

URLEncode2

CString URLEncode2(CString sIn)
{
    CString sOut;
	
    const int nLen = sIn.GetLength() + 1;

    register LPBYTE pOutTmp = NULL;
    LPBYTE pOutBuf = NULL;
    register LPBYTE pInTmp = NULL;
    LPBYTE pInBuf =(LPBYTE)sIn.GetBuffer(nLen);
    BYTE b = 0;
	
    //alloc out buffer
    pOutBuf = (LPBYTE)sOut.GetBuffer(nLen  * 3 - 2);//new BYTE [nLen  * 3];

    if(pOutBuf)
    {
        pInTmp	= pInBuf;
	pOutTmp = pOutBuf;
		
	// do encoding
	while (*pInTmp)
	{
	    if(isalnum(*pInTmp))
	        *pOutTmp++ = *pInTmp;
	    else
	        if(isspace(*pInTmp))
		    *pOutTmp++ = '+';
		else
		{
		    *pOutTmp++ = '%';
		    *pOutTmp++ = toHex(*pInTmp>>4);
		    *pOutTmp++ = toHex(*pInTmp%16);
		}
	    pInTmp++;
	}
	*pOutTmp = '\0';
	//sOut=pOutBuf;
	//delete [] pOutBuf;
	sOut.ReleaseBuffer();
    }
    sIn.ReleaseBuffer();
    return sOut;
}

Modifications

26.06.2001 - changed out buffer memory allocation (thx 2 Marc Brooks and Matthias)

License

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A list of licenses authors might use can be found here


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Comments and Discussions

 
QuestionThis is slightly broke, and to clear up some confussion Pin
KevinSW21-Sep-12 1:35
KevinSW21-Sep-12 1:35 
GeneralHere's a much simpler method that supports Unicode Pin
dc_200025-Apr-11 0:59
dc_200025-Apr-11 0:59 
Questionwtf is "if (!isalnum(*pInTmp) && !isalnum(*pInTmp))" ? Pin
s98769026-Jul-07 23:34
s98769026-Jul-07 23:34 
GeneralURLEncode2() Unicode version Pin
mcanti2-May-06 2:28
mcanti2-May-06 2:28 
GeneralUnicode solution Pin
angelo moscati4-Jul-05 3:41
angelo moscati4-Jul-05 3:41 
GeneralRe: Unicode solution Pin
angelo moscati4-Jul-05 5:24
angelo moscati4-Jul-05 5:24 
I had a bug in the last post.

inline TCHAR toHex(const BYTE &x)
{
return x > 9 ? _T('A') + x-10: _T('0') + x;
}

CString URLEncode2(CString sIn)
{
CString sOut;

const int nLen = sIn.GetLength();
// do encoding
for (int i = 0; i <nlen; i++)="" {
="" tchar="" c="sIn.GetAt(i);

" if(_istalnum(c))
="" sout.appendchar(c);
="" else
="" if(_istspace(c))
="" sout.appendchar(_t('+'));
="" int="" ic="_TINT(c);"
="" sout.appendchar(_t('%'));
="" sout.appendchar(tohex((byte)(ic="">>4)));
sOut.AppendChar(toHex((BYTE)(ic%16)));
}
}
sOut.AppendChar(_T('\0'));
return sOut;
}
GeneralNot support UNICODE Pin
chinkuanyeh10-Oct-04 21:28
chinkuanyeh10-Oct-04 21:28 
GeneralCR LF support Pin
little.mole3-Jul-04 10:29
little.mole3-Jul-04 10:29 
Questionmistake? Pin
3m2u16-Mar-04 23:02
3m2u16-Mar-04 23:02 
Questionhow to converts a string that has been encoded for transmission in a URL into a decoded string? Pin
rafaelcn24-Mar-03 6:25
rafaelcn24-Mar-03 6:25 
AnswerRe: how to converts a string that has been encoded for transmission in a URL into a decoded string? Pin
little.mole3-Jul-04 11:23
little.mole3-Jul-04 11:23 
QuestionUnicode? Pin
AlexMarbus6-Nov-02 3:11
AlexMarbus6-Nov-02 3:11 
Generalnot portable Pin
pamela7-Oct-01 2:42
pamela7-Oct-01 2:42 
GeneralRe: not portable Pin
Anonymous17-May-03 9:15
Anonymous17-May-03 9:15 
QuestionHow to add a dialog before Windows's explore working Pin
12-Jul-01 14:48
suss12-Jul-01 14:48 
GeneralWindows already does (most) of this, methinks... Pin
Arnt Witteveen4-Jul-01 0:57
Arnt Witteveen4-Jul-01 0:57 
GeneralRe: Windows already does (most) of this, methinks... Pin
Ryszard Krakowiak9-Jul-01 4:35
Ryszard Krakowiak9-Jul-01 4:35 
GeneralRe: Windows already does (most) of this, methinks... Pin
23-Jul-01 15:29
suss23-Jul-01 15:29 
GeneralRe: Windows already does (most) of this, methinks... Pin
Anonymous29-Aug-02 1:29
Anonymous29-Aug-02 1:29 
GeneralMinor correction in UrlEncode1 Pin
Marc Brooks25-Jun-01 18:14
Marc Brooks25-Jun-01 18:14 
GeneralGetBuffer instead of new Pin
25-Jun-01 5:08
suss25-Jun-01 5:08 
GeneralGetBuffer instead of new Pin
25-Jun-01 5:08
suss25-Jun-01 5:08 
GeneralRe: GetBuffer instead of new Pin
Wictor Wilén1-Aug-01 10:59
Wictor Wilén1-Aug-01 10:59 

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