static int tolow(int c)
{
if (c >= 'A' && c <= 'Z')
{
return c + 'a' - 'A';
}
else
{
return c;
}
}
static int htoi(char s[])
{
int i;
int n = 0;
if (s[0] == '0' && (s[1]=='x' || s[1]=='X'))
{
i = 2;
}
else
{
i = 0;
}
for (; (s[i] >= '0' && s[i] <= '9') || (s[i] >= 'a' && s[i] <= 'z') || (s[i] >='A' && s[i] <= 'Z');++i)
{
if (tolow(s[i]) > '9')
{
n = 16 * n + (10 + tolow(s[i]) - 'a');
}
else
{
n = 16 * n + (tolow(s[i]) - '0');
}
}
return n;
}
将十六进制字符串转换成可用十六进制表示的数字
