标准ANSI C函数函数介绍

读取16进制字符串函数：strtol

_CRTIMP long __cdecl strtol(const char *, char **, int); // stdlib.h

void HexStrToBinary(BYTE* data, int buf_len, const char * hex_str)

{

char * pHex = (char *)hex_str;

BYTE * pBuf = data;

int len = 0;

while(pHex && pHex[0] && pHex[1] && (len++ < buf_len))

{

*pBuf++ = (char)strtol(pHex, &pHex, 16);

}

*pBuf = '/0';

}

void BinaryToHexStr(char * hex_str, const BYTE* data, int len)

{

char * pHex = (char *)hex_str;

const byte * pData = data;

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

{

sprintf(pHex, "%02x ", (byte)(*pData));

pData ++;

pHex += 3;

}

*pHex = '/0';

}

上述方法适合从文件里面读入一大串16进制字符串数据的转换，
如果数量很少而且是已知的，也可以这样转换：
 

char * pStr = "5E 34 7A";

int n[3] = {0};

sscanf(pStr, "%x %x %x", &n[0], &n[1], &n[2]);

_CRTIMP long __cdecl strtol(const char *, char **, int); // stdlib.h

void HexStrToBinary(BYTE* data, int buf_len, const char * hex_str)

{

char * pHex = (char *)hex_str;

BYTE * pBuf = data;

int len = 0;

while(pHex && pHex[0] && pHex[1] && (len++ < buf_len))

{

*pBuf++ = (char)strtol(pHex, &pHex, 16);

}

*pBuf = '/0';

}

void BinaryToHexStr(char * hex_str, const BYTE* data, int len)

{

char * pHex = (char *)hex_str;

const byte * pData = data;

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

{

sprintf(pHex, "%02x ", (byte)(*pData));

pData ++;

pHex += 3;

}

*pHex = '/0';

}

上述方法适合从文件里面读入一大串16进制字符串数据的转换，
如果数量很少而且是已知的，也可以这样转换：
 

char * pStr = "5E 34 7A";

int n[3] = {0};

sscanf(pStr, "%x %x %x", &n[0], &n[1], &n[2]);