C语言十六进制数据同字符串的相互转换

#include "stdafx.h"

#include <string>

#include <iostream>

#include <cctype>

#include <algorithm>

/*

入口参数：pSrc 源十六进制数据

出口参数：dest 存放运算结果

返回：true 转换成功

false 失败

*/

bool
Hex2String(unsigned
char
*pSrc,std::string &dest,
int
nL)

{

char
buf[256];

memset((char
*)buf,0,
sizeof
(buf));

unsigned char
hb;

unsigned char
lb;

for
(
int
i=0;i<nL;i++)

{

hb=(pSrc[i]&0xf0)>>4;

if
( hb>=0 && hb<=9 )

hb += 0x30;

else

if
( hb>=10 &&hb <=15 )

hb = hb -10 + 'A'
;

else

return

false
;

lb = pSrc[i]&0x0f;

if
( lb>=0 && lb<=9 )

lb += 0x30;

else

if
( lb>=10 && lb<=15 )

lb = lb - 10 + 'A'
;

else

return

false
;

buf[i*2] = hb;

buf[i*2+1] = lb;

}

dest = buf;

return

true
;

}

/*

入口参数：src 源字符串

出口参数：dest 存放运算结果

返回：true 转换成功

false 失败

*/

bool
String2Hex(std::string &src,unsigned
char
*dest)

{

unsigned char
hb;

unsigned char
lb;

if
(src.size()%2!=0)

return

false
;

transform(src.begin(), src.end(), src.begin(), toupper);

for
(
int
i=0, j=0;i<src.size();i++)

{

hb=src[i];

if
( hb>=
'A'
&& hb<=
'F'
)

hb = hb - 'A'
+ 10;

else

if
( hb>=
'0'
&& hb<=
'9'
)

hb = hb - '0'
;

else

return

false
;

i++;

lb=src[i];

if
( lb>=
'A'
&& lb<=
'F'
)

lb = lb - 'A'
+ 10;

else

if
( lb>=
'0'
&& lb<=
'9'
)

lb = lb - '0'
;

else

return

false
;

dest[j++]=(hb<<4)|(lb);

}

return

true
;

}

//下面是使用举例，在VisualStudio2008+SP1中调试通
过

int
_tmain(
int
argc, _TCHAR* argv[])

{

unsigned char
srcB[]={0x12,0x34,0x56,0x78,0x90,0xab,0xbc,0xcd,0xde,0xef};

std::string strDest;

Hex2String(srcB,strDest,sizeof
(srcB));

std::cout<<"HexToString:"
<<strDest<<std::endl;

if
(String2Hex(strDest,srcB))

std::cout<<"StringToHex:Success!"
<<std::endl;

else

std::cout<<"StringToHex:Failed!"
<<std::endl;

return
0;

}