How to convert char* byte[ ] to array?

[ikbel borcheni]

Hi, how can I convert a char* to a byte array. I tried this

unsigned Serveur::CharToByte(char in )
 {
   switch(in){
  case'0': case'1': case'2': case'3': case'4': case'5':    case'6':case'7': case'8': case'9': return (in-'0');
  case'A':case'B': case'C':case'D': case'E':case'F':return(in-'A'+10);
 
  }
 }
 
 

I used the inverse function byteToChar to display the result :

void Serveur::BytesToChar(char* destination, BYTE* source, int longueur)
{
    char chiffres[]="0123456789ABCDEF";
    int i;
    for(i=0; i<longueur; i++)
    {
        destination[i*2]=chiffres[source[i] >> 4];
        destination[i*2+1]=chiffres[source[i]& 0x0F];
    }
    destination[i*2]=0;
 
}
 

if I try the execution with the string

000100000006FF01007B000C
 

the displayed result is:

00000110000000000000066F
 

thanhs for help

[donbock]

What is type BYTE in BytesToChar?

Why does CharToByte return unsigned instead of BYTE or int?

The index into chiffres must be between 0 and 15. Line 8 honors that constraint, line 7 does not.

[ikbel borcheni]

BYTE is an unsigned char
the function CharToByte returns unsigned because a byte contains normally 2 char:

while(i<len_buffer)
    {
      x=CharToByte(buffer[i]);
      y=CharToByte(buffer[i+1]);
      byte_buffer[j]=((x<<4) | y);
      j++;
      i++;
    }
 

for the function BytesToChar, I'm sure that it works well because I tested it seperately before using it here

[donbock]

You're not quite providing enough information.

In your second post,
What are the types of buffer, x, y, and byte_buffer?
(I assume i and j are both ints.)

In your second post, shouldn't you be incrementing i by 2?

[Banfa]

This line of code

  case'A':case'B': case'C':case'D': case'E':case'F':return(in-'A'+10);

is not truly portable because you are reliant on the execution character set to ensure that 'A', 'B', 'C', 'D', 'E' and 'F' are contiguous and not the C standard and those letters are not contiguous in all execution character sets although there are in one of the most common ones (ASCII).

[donbock]

For example, the snippet Banfa points at would not work if the underlying character representation were EBCDIC. EBCDIC is not as common as ASCII, but it still crops up from time to time.

[ikbel borcheni]

I found the problem, as donbock said I have to increment i by 2 not by 1. Thanks for all