Generating a random numbers and letters

Question

Can I ask for a certain code on how to generate a random letters and numbers in one word. I know there\'s a PHP function rand(), but I don\'t know if it\'s also applicable w

Answer 1

Step 1: Create an alphabet, $alph = "0123456789abcde...";.

Step 2: Create a random number, $n = rand(0, ALPHSIZE-1);, or use mt_rand().

Step 3: Get the appropriate index in the alphabet: $alph[n];

Rinse and repeat steps 2 and 3 for as many times as you need characters.

If you want strong statistical properties (like uniformness), you should work a little harder with the random number, but this should get you started. (I think the statistical properties of that should be sufficient.)

---

OK, might as well spell it out:

$alph = "012...";
function make_random_string($N)
{
  $s = "";
  for ($i = 0; $i != $N; ++$i)
    s .= $alph[mt_rand(0, ALPHSIZE - 1)];
  return $s;
}

And here's the version that takes a custom alphabet:

function make_random_custom_string($N, $alphabet)
{
  $s = "";
  for ($i = 0; $i != $N; ++$i)
    s .= $alphabet[mt_rand(0, strlen($alphabet) - 1)];
  return $s;
}

Example: 10 random odd digits: make_random_custom_string(10, "13579");

Answer 2

Try this, it worked for me.

$numLenth = 35;

function make_seed_Token() {
  list($usec, $sec) = explode(' ', microtime());
  return (float) $sec + ((float) $usec * 100000);
}

srand(make_seed_Token());

$numSeed = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$getNumber = "";
for($i = 0; $i < $numLenth; $i ++) {
 $getNumber .= $numSeed[rand(0, strlen($numSeed))];

}

echo $getNumber;

Answer 3

I put together a PHP class for generating random numbers and strings PHPRandomValue,

It uses "mcrypt_create_iv(4, MCRYPT_DEV_URANDOM)" to generate random numbers and values. I made it while working on a crypto project because I needed a safe random value generator and mt_rand() doesn't meet that requirement. Here's an example usage

$randomValue = new RandomValue;

$randomValue->randomNumber(): = -3880998

$randomValue->randomNumberBetween(1,10): = 2

$randomValue->randomTextString(): = CfCkKDHRgUULdGWcSqP4

$randomValue->randomTextString(10):  = LorPIxaeEY

$randomValue->randomKey(): = C7al8tX9.gqYLf2ImVt/!$NOY79T5sNCT/6Q.$!.6Gf/Q5zpa3

$randomValue->randomKey(10):  = RDV.dc6Ai/

Answer 4

Use uniqid

$desired_length = 10; //or whatever length you want
$unique = uniqid();

$your_random_word = substr($unique, 0, $desired_length);

Answer 5

It might be done this way:

function RandomCode($length = 10)
{
    $code = '';
    $total = 0;

    do
    {
        if (rand(0, 1) == 0)
        {
            $code.= chr(rand(97, 122)); // ASCII code from **a(97)** to **z(122)**
        }
        else
        {
            $code.= rand(0, 9); // Numbers!!
        }
        $total++;
    } while ($total < $length);

    return $code;
}

Answer 6

function randText($len=4){
    $str = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
    for($i=0;$i<$len;$i++){
        $txt.=substr($str, rand(0, strlen($str)), 1);   
    }
return $txt;
}

to use simply type:

$yourVar = randText(10);  // to get 10char long text