creating a random string without duplicate characters php

Question

I need to create a random 15 character string without duplicate characters using php, these characters are numbers only ranging from 0 - 90 for example my the generated string would look like: 10, 44, 88, 1, 30 and so on. What would be the best way to do this?

So... As I understand it, you want to create a 15 characters long string, and none of them must have a duplicate, and you intend to do this, with 10 different numbers? — Epodax, Apr 22 '15 at 08:21
possible duplicate of [PHP random string generator](http://stackoverflow.com/questions/4356289/php-random-string-generator) — Ahmed Ziani, Apr 22 '15 at 08:23
Thats correct the numbers i want in my string must be between 0 and 90 and the string itself must be 15 characters long without duplicate numbers. — MegaDallion2, Apr 22 '15 at 08:27
@MegaDallion2 Isn't it an option to random 15 times, check if the number is the same as one of the previous ones and then get them all together seperated by a comma? — Loko, Apr 22 '15 at 09:01
the commas are just to seperate the numbers in my example not part of the string sorry — MegaDallion2, Apr 22 '15 at 09:12

score 0 · Accepted Answer · answered Apr 22 '15 at 09:21

I've got this now:

$string='';
for($i=0;$i<15; $i++){
   $number[$i]=mt_rand(0, 90);
   if(in_array($number[$i],$number)){
        //Randomned number already exists
   }else{
        //Randomned number doesn't exist yet
   }

   $string.=$number[$i].',';
}
var_dump($string);

You should check if it exists yet or not yourself. Just for educational purposes, I'm using: mt_rand(); and in_array();. mt_rand(x,y); provides a random number between x and y. in_array(x,y); checks if the value(x) exists in the array(y).

creating a random string without duplicate characters php

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