PHP function array_rand that rearranges the elements in an array in random order

Random extraction is to scramble the elements of the original array and output them. This means that after each execution, the order or elements of the extraction are different. This function can be used to display different advertisements on the web page each time. Use the shuffle() function to implement random extraction from the array:

<?php
    $textArray = array(&#39;1&#39;,&#39;2&#39;,&#39;3&#39;,&#39;4&#39;,&#39;5&#39;,&#39;6&#39;,&#39;7&#39;);
    shuffle($textArray);
    print_r($textArray);
?>

The results are shown below:

Array ( [0] => 6 [1] => 3 [2] => 7 [3] => 4 [4] => 1 [5] => 2 [6] => 5 )

The random sorting of array elements implemented;

In addition PHP also provides a function for randomly extracting values ​​from an array: array_rand(). Its calling format is as follows:

array_rand(, [number of extracted elements]);

<?php
    $arry = array(&#39;A&#39;,&#39;B&#39;,&#39;C&#39;,&#39;D&#39;);
    $result = array_rand($arry,2);
    foreach ($result as $val) {
    echo $arry["$val"].""; }
?>

The results are displayed as follows: B C Refresh has different results;

Returns an array containing random key names:

<?php
    $a=array("red","green","blue","yellow","brown");
    $random_keys=array_rand($a,3);echo $a[$random_keys[0]]."<br>";
    echo $a[$random_keys[1]]."<br>";echo $a[$random_keys[2]];
  ?>

Definition and usage

array_rand() function returns a random key name in the array, or if the specified function returns more than one key name, returns a random key name array.

Syntax

array_rand(array,number)

Parameters Description

array Required. Specifies an array.

number Optional. Specifies how many random elements to return.

Return value:

Returns a random key name in the array, or if the specified function returns more than one key name, returns an array containing random key names.

Returns a random key name in the array:

<?php
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,1));
?>

Returns an array containing a random string key name:

<?php
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,2));
?>

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