why is there no reverse string function in c#?? Is there realy no need for that function??
there are of course a few ways to make your own reverse function. most favorite is definitly the one using recursion with substring. that's preety cool i thought why not... and then i remembered something that i learned in my first year of college... bitwise operations. i knew that there was a handy little way of switching 2 values using something with XOR without using a 3rd variable. i just couldn't remember it... so i went googling... it sure was faster than going through my books :)) and voila... XOR 2 values bitwise 3 times and they're switched.
So i metion this to a friend of mine... a soon to be a computer science graduate... and he looks at me with a blank stare... so i go about explaining it and he goes: huh??
so why are bitwise operation so hard to understand?? are they too hard to grasp???
well for anyone who wants it :) here's the reverse function:

public string Reverse(string str)
{
    // convert the string to char array
    char[] charArray = str.ToCharArray();
    int len = str.Length - 1;
    /*
    now this for is a bit unconventional at first glance because there
    are 2 variables that we're changing values of: i++ and len--.
    the order of them is irrelevant. so basicaly we're going with i from 
    start to end of the array. with len we're shortening the array by one
    each time. this is probably understandable.
    */
    for (int i = 0; i < len; i++, len--)
    {
        /*
        now this is the tricky part people that should know about it don't.
        look at the table below to see what's going on exactly here.
        */
        charArray[i] ^= charArray[len];
        charArray[len] ^= charArray[i];
        charArray[i] ^= charArray[len];
    }
    return new string(charArray);
}

in c# x1 ^= x2 equals to x1 = x1 ^ x2 where ^ is the bitwise XOR.

EDIT:

Well after Arnold pointed me to this site i came up with this:

public string Reverse2(string x)
{
    char[] charArray = new char[x.Length];
    int len = x.Length - 1;
    for (int i = 0; i <= len; i++)
        charArray[i] = x[len-i];
    return new string(charArray);
}

This one is even faster than XOR on small as well as large strings by 50%. Looking at the algorithm is preety evident where the speed is gained:

char[] charArray = new char[x.Length];

for (int i = 0; i <= len; i++) 
    charArray[i] = x[len-i];

Arnold if you have any check for surrogate pairs you can share i'm all ears (eyes). :))