Question

I am looking to generate a random string based on the amount of products I have. For instance I have 100 products named “test” I want to be able to generate 100 product codes which will all be unique.

I am currently using this code:

<?php   
/**
* The letter l (lowercase L) and the number 1
* have been removed, as they can be mistaken
* for each other.
*/

function createRandomPassword() {
    $chars = "abcdefghijkmnopqrstuvwxyz023456789";
    srand((double)microtime()*1000000);
    $i = 0;
    $pass = '' ;
    while ($i <= 7) {
        $num = rand() % 33;
        $tmp = substr($chars, $num, 1);
        $pass = $pass . $tmp;
        $i++;
    }
    return $pass;
}
// Usage
$password = createRandomPassword();
echo "Your random password is: $password";
?>

Cheers

Answer 1

There is already a built in function that will handle this for you trivially. uniqid generates a prefixed unique identifier based on the current time in microseconds.

http://php.net/manual/en/function.uniqid.php

<?php
// loop 100 times
for ($i=0; $i<100; $i++)
{
  // print the uniqid based on 'test'
  echo uniqid('test', true);
}
?>

It is worth noting that to ensure true uniqueness you would need to store all the codes generated and check that no duplicated are issued.