generate random numbers in php with no repeats

random number generation, no repeats

function randomDigits($length){
    $numbers = range(0,9);
    shuffle($numbers);
    for($i = 0;$i < $length;$i++)
       $digits .= $numbers[$i];
    return $digits;
}

i got error undefined $digits variable ^^

Hi

you should to give a value to variable before loop

Like this :

function randomDigits($length){
$numbers = range(0,9);
shuffle($numbers);
$digits = "";
for($i = 0;$i < $length;$i++)
$digits .= $numbers[$i];
return $digits;
}

Getting the same error.

Problem solved

$digits = '';
function randomDigits($length){
    $numbers = range(0,9);
    shuffle($numbers);
    for($i = 0; $i < $length; $i++){
    	global $digits;
       	$digits .= $numbers[$i];
    }
    return $digits;
}

`

How can i authenticated this against database values?

BS

How can i authenticated this against database values?

You can just search the value in your database, if it returns null then it has not been stored yet.

just doing like that
function randomDigits($length){ // function with parameter you must define it before callback the function
global $digits; // global to access from anyway
$numbers = range(0,9);
shuffle($numbers);
for($i = 0;$i < $length;$i++)
$digits .= $numbers[$i];
return $digits;
}
echo randomDigits(4); // 4 mean your number between 4 digits