C/C++: Converting hexadecimal value in char to integer

Question

I have hexadecimal values stored as characters:

char A = \'0\';
char B = \'6\';
char C = \'E\';

... I need them coverted to integers. I kno

Answer 1

In C:

const char chrs[] = "0123456789ABCDEF";

int value = -1; // sentinel
const char *loc = strchr(chrs, ch);
if (loc)
    value = loc - chrs;

or, using C++:

const std::string chrs("0123456789ABCDEF");
int value = chrs.find(ch);