PHP: How to generate a random, unique, alphanumeric string for use in a secret link?

Question

How would it be possible to generate a random, unique string using numbers and letters for use in a verify link? Like when you create an account on a website, and it sends y

Answer 1

Here is ultimate unique id generator for you. made by me.

<?php
$d=date ("d");
$m=date ("m");
$y=date ("Y");
$t=time();
$dmt=$d+$m+$y+$t;    
$ran= rand(0,10000000);
$dmtran= $dmt+$ran;
$un=  uniqid();
$dmtun = $dmt.$un;
$mdun = md5($dmtran.$un);
$sort=substr($mdun, 16); // if you want sort length code.

echo $mdun;
?>

you can echo any 'var' for your id as you like. but $mdun is better, you can replace md5 to sha1 for better code but that will be very long which may you dont need.

Thank you.

Answer 2

Use the code below to generate the random number of 11 characters or change the number as per your requirement.

$randomNum=substr(str_shuffle("0123456789abcdefghijklmnopqrstvwxyz"), 0, 11);

or we can use custom function to generate the random number

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

 //generate random number
 $randomNum=randomNumber(11);

Answer 3

after reading previous examples I came up with this:

protected static $nonce_length = 32;

public static function getNonce()
{
    $chars = array();
    for ($i = 0; $i < 10; $i++)
        $chars = array_merge($chars, range(0, 9), range('A', 'Z'));
    shuffle($chars);
    $start = mt_rand(0, count($chars) - self::$nonce_length);
    return substr(join('', $chars), $start, self::$nonce_length);
}

I duplicate 10 times the array[0-9,A-Z] and shuffle the elements, after I get a random start point for substr() to be more 'creative' :) you can add [a-z] and other elements to array, duplicate more or less, be more creative than me

Answer 4

You can use this code, I hope it will be helpful for you.

function rand_code($len)
{
 $min_lenght= 0;
 $max_lenght = 100;
 $bigL = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 $smallL = "abcdefghijklmnopqrstuvwxyz";
 $number = "0123456789";
 $bigB = str_shuffle($bigL);
 $smallS = str_shuffle($smallL);
 $numberS = str_shuffle($number);
 $subA = substr($bigB,0,5);
 $subB = substr($bigB,6,5);
 $subC = substr($bigB,10,5);
 $subD = substr($smallS,0,5);
 $subE = substr($smallS,6,5);
 $subF = substr($smallS,10,5);
 $subG = substr($numberS,0,5);
 $subH = substr($numberS,6,5);
 $subI = substr($numberS,10,5);
 $RandCode1 = str_shuffle($subA.$subD.$subB.$subF.$subC.$subE);
 $RandCode2 = str_shuffle($RandCode1);
 $RandCode = $RandCode1.$RandCode2;
 if ($len>$min_lenght && $len<$max_lenght)
 {
 $CodeEX = substr($RandCode,0,$len);
 }
 else
 {
 $CodeEX = $RandCode;
 }
 return $CodeEX;
}

Details about Random code generator in PHP