C语言判断字符串是否是 hex string

C语言判断字符串是否是 hex string

BOOL is_hex_string(char *str)
{
	static unsigned int hex2bin[256]={0};
	memset(hex2bin,0xFF,256);
	hex2bin['1'] = 1;
	hex2bin['2'] = 2;
	hex2bin['3'] = 3;
	hex2bin['4'] = 4;
	hex2bin['5'] = 5;
	hex2bin['6'] = 6;
	hex2bin['7'] = 7;
	hex2bin['8'] = 8;
	hex2bin['9'] = 9;
	hex2bin['0'] = 0;
	hex2bin['a'] = 0xa;
	hex2bin['b'] = 0xb;
	hex2bin['c'] = 0xc;
	hex2bin['d'] = 0xd;
	hex2bin['e'] = 0xe;
	hex2bin['f'] = 0xf;
	hex2bin['A'] = 0xA;
	hex2bin['B'] = 0xB;
	hex2bin['C'] = 0xC;
	hex2bin['D'] = 0xC;
	hex2bin['E'] = 0xE;
	hex2bin['F'] = 0xF;
	while(*str)
	{
		if(hex2bin[*str] > 0xF)
			return FALSE;
	}
	return TRUE;
}