<?
$l='a'; //Set the starting letter
for($i=0;$i<26;$i++){ //Cycle through all of the letters of the alphabet a-z
$key[$i]=$l; //Load the array with lowercase variables at position $i
$l++; //Increment the letter
}
for($x=0;$x<5;$x++){ //Cycle through this five times. The more you cycle through this loop the more likely a number will appear.
for($n=0;$n<10;$n++){ //Cycle through the numbers 0-9
$key[$i]=$n; //Load the array with number variables at position $i
$i++; //Increment the array key
}
}
$u='A'; //Set the starting letter
for($c=0;$c<26;$c++){ //Cycle through all of the letters of the alphabet A-Z
$key[$i]=$u; //Load the array with uppercase variables
$i++; //Increment the array key
$u++; //Increment the letter
}
$i--; //Subtract the last incrementation of $i because it's not indexed
$str='';
for($strlength=0;$strlength<20;$strlength++){ //Generate the random string 20 characters long
//$r = rand(0,$i); //Generate a random number from the available $i interger
$r = rand()&$i; //Generate a random number from the available $i interger using bitwise
$str .= $key[$r]; //Concatenate the random variable
}
echo $str; //Show the random string
?>