Convert char with hex value to String

Question

If I have a character like the following:

wchar_t c = '\x0A'

What's an easy way to convert it so that it becomes something like:

wchar_t dst[] ==> "0A"

Basically, the hex value of c becomes a string value.

Answer 1

The integral value of c would be 0x0A (10 in base 10). You can use sprintf to format it as hex:

wchar_t c = '\x0A';
int c_val = c;
char string[3];

sprintf( string, "%.2X", c_val );

Note the intermediate c_val variable is not needed, only added for clarity

or you can do it manually:

int c_low = c & 0x0F;
int c_high = ( c & 0xF0 ) >> 4;

...translate c_low and c_high to its textual representation...

Answer 2

A simple hexifier can be written quite easily. This one takes the target string as an input parameter:

unsigned int hexify(const wchar_t * src, char * dst, unsigned int dstlen)
{
  static const char alphabet[] = "0123456789ABCDEF";

  unsigned int i = 0;
  while (*src && 2*i + 1 < dstlen)
  {
    dst[2*i]   = alphabet[*src / 16];
    dst[2*i+1] = alphabet[*src % 16];
    ++src;
    ++i;
  }
  dst[2*i] = 0;
  return i;
}

Usage:

char s[100];
hexify(some_wstr, s, 100);