How to reverse sort an array in php without retaining key names

Implementation steps: 1. Use the array_reverse() function to reverse sort the array. The syntax "array_reverse (original array)" will return a reverse array; 2. Use the array_values() function to reset the keys of the reverse array. Name, syntax "array_values ​​(reverse array)", the returned array will use numerical keys, starting from 0 and increasing by 1.

The operating environment of this tutorial: windows7 system, PHP version 8.1, DELL G3 computer

In php, you can use array_reverse() and The array_values() function sorts the array in reverse order without retaining the key names.

Implementation steps:

Step 1: Use array_reverse() function to reverse sort the array

array_reverse() function Returns an array in reverse element order.

array_reverse($array,$preserve)

Parameters	Description
array	Required . Specifies an array.
preserve	Optional. Specifies whether to retain the original array key names. If set to TRUE, numeric keys will be preserved. Non-numeric keys are not affected by this setting and will always be retained. This parameter is newly added in PHP 4.0.3. Possible values: true false

##If If the two parameters

$preserve are specified as true, the numeric key name of the element will remain unchanged, otherwise the numeric key name will be lost (the index starts from 0 and increases by 1).

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);   
$a=array("Volvo","XC90","BMW","Toyota");
$reverse=array_reverse($a);
$preserve=array_reverse($a,true);

var_dump($a);
var_dump($reverse);
var_dump($preserve);
?>

The second parameter $preserve is invalid for associative arrays and the key name cannot be reset.

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);   
$a=array("Name"=>"Peter","Age"=>"41","Country"=>"USA");
$reverse=array_reverse($a);
var_dump($a);
var_dump($reverse);
?>

So the array_values() function is needed.

Step 2: Use the array_values() function to reset the key name of the reverse array (the key name will become a numeric type, starting from 0 and increasing by 1)

The array_values() function returns an array containing all the values ​​in the array.

Tip: The returned array will use numeric keys, starting from 0 and increasing by 1.

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);   
$a=array("Name"=>"Peter","Age"=>"41","Country"=>"USA");
$reverse=array_reverse($a);
var_dump($a);
var_dump($reverse);

$res=array_values($reverse);
var_dump($res);
?>

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