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HomeBackend DevelopmentPHP TutorialFive ways to generate non-repetitive random numbers in PHP

Five ways to generate non-repetitive random numbers in PHP

Nov 10, 2017 pm 02:15 PM
phpWayrandom number

In the previous article, I introduced the method of generating random numbers in PHP. We all know that PHP random numbers are an indispensable part whether in development or in mobile applications. They are often used in daily development. Dealing with PHP random numbers, so today I will introduce to you five ways to generate PHP random numbers without repetition!

The first way:

<?php 
$numbers = range (1,50); 
//shuffle 将数组顺序随即打乱 
shuffle ($numbers); 
//array_slice 取该数组中的某一段 
$num=6; 
$result = array_slice($numbers,0,$num); 
print_r($result); 
?>

The second way

<?php 
$numbers = range (1,20); 
//播下随机数发生器种子,可有可无,测试后对结果没有影响
srand ((float)microtime()*1000000); 
shuffle ($numbers); 
//跳过list第一个值(保存的是索引)
while (list(, $number) = each ($numbers)) { 
echo "$number "; 
} 
?>

The third way

<?php 
function NoRand($begin=0,$end=20,$limit=5){ 
$rand_array=range($begin,$end); 
shuffle($rand_array);//调用现成的数组随机排列函数 
return array_slice($rand_array,0,$limit);//截取前$limit个 
} 
print_r(NoRand()); 
?>


The above can generate 5 non-repeating php random numbers between 1-20

The fourth way

<?php 
$tmp=array(); 
while(count($tmp)<5){ 
$tmp[]=mt_rand(1,20); 
$tmp=array_unique($tmp); 
} 
print_r($tmp);
?>


The fifth way

<?php 
$tmp = range(1,30);
print_r(array_rand($tmp,10));
?>

This may be simpler than calling (ps: If the step is specified in the range long, you must pay attention to whether the second parameter of array_rand exceeds the length of $tmp).

Summary:

PHP provides a very rich set of array functions. Most PHP random numbers can be generated from the perspective of arrays. Of course If you have a better method, I hope it will be helpful to you. This article can be considered as a starting point.

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php random number generation method


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##php random number WeChat Red envelope random generation algorithm php version


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