How to generate unique numbers in php

The way PHP generates unique numbers is through the mt_rand() function. Function syntax: [mt_rand(min,max)], such as [mt_rand(10,100)], means generating a random integer between 10 and 100 (inclusive).

#To generate unique numbers, you can use the mt_rand() function.
(Recommended tutorial: php tutorial)

Function introduction:

mt_rand() function uses the Mersenne Twister algorithm to generate random integers.

For example:

If you want a random integer between 10 and 100, inclusive, use mt_rand (10,100).

Function syntax:

mt_rand();
or
mt_rand(min,max);

Parameter introduction:

• min Optional. Specifies the minimum number to return. The default is 0.

• max Optional. Specifies the maximum number to return. The default is mt_getrandmax().

Code implementation:

<?php
/*
* array unique_rand( int $min, int $max, int $num )
* 生成一定数量的不重复随机数，指定的范围内整数的数量必须
* 比要生成的随机数数量大
* $min 和 $max: 指定随机数的范围
* $num: 指定生成数量
*/
function unique_rand($min, $max, $num) {
  $count = 0;
  $return = array();
  while ($count < $num) {
    $return[] = mt_rand($min, $max);
    $return = array_flip(array_flip($return));
    $count = count($return);
  }
  //打乱数组，重新赋予数组新的下标
  shuffle($return);
  return $return;
}

//生成10个1到100范围内的不重复随机数
$arr = unique_rand(1, 100, 10);
echo implode($arr, ",");
?>

The above is the detailed content of How to generate unique numbers in php. For more information, please follow other related articles on the PHP Chinese website!