Random number in range [min - max] using PHP
PhpSecurityRandomPhp Problem Overview
Is there a way to generate a random number based on a min and max?
For example, if min was 1 and max 20 it should generate any number between 1 and 20, including 1 and 20?
Php Solutions
Solution 1 - Php
<?php
$min=1;
$max=20;
echo rand($min,$max);
?>
Solution 2 - Php
In a new PHP7 there is a finally a support for a cryptographically secure pseudo-random integers.
int random_int ( int $min , int $max )
> random_int — Generates cryptographically secure pseudo-random integers
which basically makes previous answers obsolete.
Solution 3 - Php
A quicker faster version would use mt_rand:
$min=1;
$max=20;
echo mt_rand($min,$max);
Source: <http://www.php.net/manual/en/function.mt-rand.php>;.
NOTE: Your server needs to have the Math PHP module enabled for this to work. If it doesn't, bug your host to enable it, or you have to use the normal (and slower) rand().
Solution 4 - Php
I have bundled the answers here and made it version independent;
function generateRandom($min = 1, $max = 20) {
if (function_exists('random_int')):
return random_int($min, $max); // more secure
elseif (function_exists('mt_rand')):
return mt_rand($min, $max); // faster
endif;
return rand($min, $max); // old
}
Solution 5 - Php
Solution 6 - Php
rand(1,20)
Docs for PHP's rand function are here:
http://php.net/manual/en/function.rand.php
Use the srand()
function to set the random number generator's seed value.
Solution 7 - Php
Try This one. It will generate id according to your wish.
function id()
{
// add limit
$id_length = 20;
// add any character / digit
$alfa = "abcdefghijklmnopqrstuvwxyz1234567890";
$token = "";
for($i = 1; $i < $id_length; $i ++) {
// generate randomly within given character/digits
@$token .= $alfa[rand(1, strlen($alfa))];
}
return $token;
}