How to sort an associative array by key in PHP
In this tutorial, we are going to see how to sort an associative array by key in PHP. The PHP functions ksort() and krsort() can be used to sort an array by key.
Sort an associative array by key in ascending order
You can use the ksort() function to sort an associative array alphabetically by key in ascending order while maintaining the relationship between key and value.
<?php $languages = array("p"=>"PHP", "j"=>"Java", "a"=>"Ada", "h"=>"HTML", "c"=>"CSS"); // Sorting the array by key ksort($languages); print_r($languages); ?>
Output:
Array ( [a] => Ada [c] => CSS [h] => HTML [j] => Java [p] => PHP )
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Sort an associative array by key in descending order
You can use the krsort() function to sort an associative array alphabetically by key in descending order, while maintaining the relationship between key and value.
<?php $langages = array("p"=>"PHP", "j"=>"Java", "a"=>"Ada", "h"=>"HTML", "c"=>"CSS"); // Sorting the array by key krsort($langages); print_r($langages); ?>
Output:
Array ( [p] => PHP [j] => Java [h] => HTML [c] => CSS [a] => Ada )[st_adsense]