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PHP

Posted by Jackie Jen
Jackie Jen
2,723 Points

generate auto increment alphanumeric strings

Below is my code

<?php
        $length = 4;
    $id = '';
    for ($i=0;$i<$length;$i++){
        $id .= rand(1, 9);

    }
echo $id;
?>

right now i only able to generate randomly of 4 digits number. But how can i add character in the 4 digits like 'AAA0001' then it automatucally increase to 'AAA9999' and start with new character ' AAB0001'.

I have no idea on it,please advice.

2 Answers

john appleseed
john appleseed
2,568 Points
john appleseed
john appleseed
2,568 Points

Hey!

$num_of_ids = 10000; //Number of "ids" to generate.
$i = 0; //Loop counter.
$n = 0; //"id" number piece.
$l = "AAA"; //"id" letter piece.

while ($i <= $num_of_ids) { 
    $id = $l . sprintf("%04d", $n); //Create "id". Sprintf pads the number to make it 4 digits.
    echo $id . "<br>"; //Print out the id.

    if ($n == 9999) { //Once the number reaches 9999, increase the letter by one and reset number to 0.
        $n = 0;
        $l++;
    }

    $i++; $n++; //Letters can be incremented the same as numbers. Adding 1 to "AAA" prints out "AAB".
}

The previous code would print out the following,

AAA0000 AAA0001 AAA0002 AAA0003 AAA0004 AAA0005 AAA0006 AAA0007 ...

Sprintf is very useful in situations like this, so I'd recommend reading more about it in the documentation. http://us2.php.net/manual/en/function.sprintf.php

Good luck!

Jackie Jen
Jackie Jen
2,723 Points
Jackie Jen
Jackie Jen
2,723 Points

Thanks alot..about the sprint function