How to sort multidimensional array in PHP while preserving key names?

Sort multi-dimensional arrays while retaining key names: 1. Use uksort() to sort according to key values, and provide a comparison function that returns 1, -1 or 0 to indicate the relative order of key values. 2. Use krsort() to sort key values ​​from high to low, accepting an array parameter.

How to sort a multidimensional array in PHP while preserving key names

Sometimes, you may need to sort a multidimensional array Sort while preserving their key names. For this purpose, PHP provides the uksort() and krsort() functions.

uksort

uksort() The function sorts an array based on the value of the array key. It accepts two parameters: an array containing the array to be sorted and a comparison function. The comparison function should return one of the following values:

• 1 if the first element of the array should come before the second element
• -1 if the first element of the array Should be
• 0 after the second element if the first element of the array is equal to the second element

<?php

$cars = [
    "Mercedes" => "Germany",
    "BMW" => "Germany",
    "Toyota" => "Japan",
    "Honda" => "Japan"
];

uksort($cars, function($a, $b) {
    return strcmp($a, $b);
});

foreach ($cars as $key => $value) {
    echo "$key: $value\n";
}

?>

Output:

BMW: Germany
Honda: Japan
Mercedes: Germany
Toyota: Japan

krsort

krsort() The function sorts the array and sorts the key values ​​from high to low. It accepts one parameter, the array to sort.

<?php

$cars = [
    "Mercedes" => "Germany",
    "BMW" => "Germany",
    "Toyota" => "Japan",
    "Honda" => "Japan"
];

krsort($cars);

foreach ($cars as $key => $value) {
    echo "$key: $value\n";
}

?>

Output:

Toyota: Japan
Honda: Japan
Mercedes: Germany
BMW: Germany

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