Tác dụng của hàm arsort()
The arsort() function sorts an associative array in descending order, according to the value.
The keys are preserved, i.e. the key-to-value mapping will remain unchanged by the sort operation.
The following table summarizes the technical details of this function.
| Return Value: | Returns TRUE on success or FALSE on failure. |
|---|---|
| Version: | PHP 4+ |
Syntax
The basic syntax of the arsort() function is given with:
The following example shows the arsort() function in action.
Example
Run this code »<?php
// Sample array
$alphabets = array("b"=>"ball", "d"=>"dog", "a"=>"apple", "c"=>"cat");
// Sorting alphabets array
arsort($alphabets);
print_r($alphabets);
?>Tip: The arsort() and asort() functions mainly used for sorting associative arrays by value, whereas krsort() and ksort() functions used for sorting associative arrays by key.
Parameters
The arsort() function accepts the following parameters.
| Parameter | Description |
|---|---|
| array | Required. Specifies the array to sort. |
| sort_flags |
Optional. Specifies how array items should be compared. Possible values are:
|
More Examples
Here're some more examples showing how arsort() function actually works:
The following example sorts an associative array having numeric values in descending order:
Example
Run this code »<?php
// Sample array
$persons = array("Harry"=>18, "Clark"=>32, "Peter"=>20, "John"=>24);
// Sorting persons array
arsort($persons);
print_r($persons);
?>