XOR Encryption

First off I appreciate any help that you all may provide. Also I made this post for two reasons. One of which being to give anyone out there wanting a XOR encryption function the chance to use this one, and also I have a question between the 2 code snippets at the bottom of the post.

The working function ( I removed the key I used for privacy, but it is easy to add your own, if you cant your hopeless)
//crypt.h

Code:

---

#include <string>
struct CRYPT_
{
    char byte;
    std::string key;
};

bool Crypt(const std::string&);

---

//crypt.cpp

Code:

---

#include "crypt.h"
#include <fstream>
using namespace std;
CRYPT_ data;
bool Crypt(const std::string& file)
{
    char savebyte;
    int value = 0;
    data.key = "type new key here";
    ifstream load (file.c_str(), ios::binary);
    if (!load)
    {
        return false;
    }
    ofstream save ("encrypted.xtc", ios::binary);
    while (load.get(data.byte))
    {
        savebyte = data.byte ^ data.key[value];
        save << savebyte;
        if ( value < 92 )
        {
            ++value;
        }
        else {
            value = 0;
        }
    }
    save.close();
    load.close();
    remove(file.c_str());
    rename("encrypted.xtc", file.c_str());
    return true;
}

---

That is for anyone that may have been looking for something like this.

Now my question is why will this work

Code:

---

while (load.get(data.byte))
    {
        savebyte = data.byte ^ data.key[value];
        save << savebyte;
        if ( value < 92 )
        {
            ++value;
        }
        else {
            value = 0;
        }
    }

---

but on the other hand this looks pretty much the same, but I get a lot of errors trying this...

Code:

---

while (load.get(data.byte))
    {
        save << data.byte ^ data.key[value];
        if ( value < 92 )
        {
            ++value;
        }
        else {
            value = 0;
        }
    }

---

Thank you very much for taking your time to assist me. Good day.

Which has more precedence, operator^ or operator<<?

I thought bitwise took precedence, but I guess I was wrong?

Quote:

---

Originally Posted by Raigne

I thought bitwise took precedence, but I guess I was wrong?

---

<< is bitwise as well. There is no precedence level called "bitwise," the bitwise operators are spread across a few levels. Get a C precedence chart, print it, tape it on the wall.

Yay, precedence chart!

http://www.cs.uml.edu/~dm/course/91....ence_chart.htm

[offtopic] Anyone like my sig? :)

so placing parenthesis would have fixed this. Got it, thanks for the help. Hopefully this helps someone.

Doubtful, most care to look at operator precedence. At least those who like the rules of maths :s