Converting string to unsigned char

Question

I've spent a while trying to get a string to turn into an array of unsigned chars, but no luck. I'm doing an AES implementation and I have everything set up except the input reading part. This is the code I have ATM.

string text = "E3 FD 51 12" ;
    int size = text.length();

    unsigned char* charText = new unsigned char[size/2];
    int i = 0;
    std::istringstream text_2(text);

    unsigned int c;
    unsigned char ch;
    while (text_2 >> hex >> c)
    {
        ch = c;
        cout <<ch;
    }

I want my string to be in the charText array. The string reads perfectly into the unsigned int, but when I try to place it in the array or in the unsigned char (ch), it gives me gibbrish.

Any help would be great.

The first two characters are outside the ASCII range, the 51 yields a `'Q'` and the last character is a form feed. You might call this gibberish but what did you expect...? — Dietmar Kühl, Nov 28 '13 at 23:25
Well, what is _correct_ if you don't like to convert these values to their character values? If you print the `char` values as `int` using `std::cout << std::hex << int(ch);` you'll get the original values back (obviously, if your values are smaller than 16 you'll need to a set up a width and a `'0'` fill character). — Dietmar Kühl, Nov 28 '13 at 23:36

score 0 · Accepted Answer · answered Nov 28 '13 at 23:31

0

Simply output the char as int.

while (text_2 >> hex >> c)
{
    ch = c;
    cout << hex << ( int )ch;
}

answered Nov 28 '13 at 23:31

Vlad from Moscow

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ok but if i store the way I am currently wont it cause issues when doing matrix multiplications? – inzombiak Nov 28 '13 at 23:37
I am sorry. I do not understand what you are speaking about. – Vlad from Moscow Nov 28 '13 at 23:58
I need to multiply the values stored with lets say 0xef – inzombiak Nov 29 '13 at 00:10

Converting string to unsigned char

1 Answers1