What functions are used in PHP to randomly shuffle an array?

The following functions in PHP can shuffle arrays randomly: shuffle() directly changes the order of array elements. array_rand() returns a random key that can rearrange the array order based on the key.

Functions for randomly shuffling arrays in PHP

In PHP, there are several functions that can be used to randomly shuffle arrays , changing the order of its elements. These functions include:

1. shuffle()

##shuffle() The function directly shuffles the incoming array and changes its internal The order of the elements.

<?php
$arr = [1, 2, 3, 4, 5];
shuffle($arr);
print_r($arr); // 输出洗牌后的数组
?>

2. array_rand()

array_rand() The function will return the specified number of random keys in the array, which can be rearranged according to these keys Array order.

<?php
$arr = [1, 2, 3, 4, 5];
$keys = array_rand($arr, 3); // 随机返回 3 个键
$sortedArr = [];
foreach ($keys as $key) {
    $sortedArr[] = $arr[$key];
}
print_r($sortedArr); // 输出重新排列后的数组
?>

Practical case:

Suppose you have a list of student names and need to be randomly assigned to different classes. You can use the following code:

<?php
$students = ['John', 'Mary', 'Bob', 'Alice', 'Tom'];
shuffle($students);
// 将学生分成 2 个班级
$class1 = array_slice($students, 0, 3);
$class2 = array_slice($students, 3);
print_r($class1); // 输出第一个班级中的学生
print_r($class2); // 输出第二个班级中的学生
?>

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