Sort an array using a case insensitive "natural order" algorithm

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- Sort an array using a case insensitive "natural order" algorithm

# ArrayObject::natcasesort

(PHP 5 >= 5.2.0, PHP 7, PHP 8)

ArrayObject::natcasesort — Sort an array using a case insensitive "natural order" algorithm

### Description

public ArrayObject::natcasesort(): true

This method is a case insensitive version of ArrayObject::natsort.

This method implements a sort algorithm that orders alphanumeric strings in the way a human being would while maintaining key/value associations. This is described as a "natural ordering".

> Note:

> If two members compare as equal, they retain their original order. Prior to PHP 8.0.0, their relative order in the sorted array was undefined.

### Parameters

This function has no parameters.

### Return Values

No value is returned.

### Changelog

Version | Description
--- | ---
8.2.0 | The return type is `true` now; previously, it was bool.

### Examples

Example #1 ArrayObject::natcasesort() example

    <?php$array = array('IMG0.png', 'img12.png', 'img10.png', 'img2.png', 'img1.png', 'IMG3.png');$arr1 = new ArrayObject($array);$arr2 = clone $arr1;$arr1->asort();echo "Standard sorting\n";print_r($arr1);$arr2->natcasesort();echo "\nNatural order sorting (case-insensitive)\n";print_r($arr2);?>

The above example will output:

    Standard sorting
    ArrayObject Object
    (
        [0] => IMG0.png
        [5] => IMG3.png
        [4] => img1.png
        [2] => img10.png
        [1] => img12.png
        [3] => img2.png
    )

    Natural order sorting (case-insensitive)
    ArrayObject Object
    (
        [0] => IMG0.png
        [4] => img1.png
        [3] => img2.png
        [5] => IMG3.png
        [2] => img10.png
        [1] => img12.png
    )

For more information see: Martin Pool's » Natural Order String Comparison page.

### See Also

- ArrayObject::asort() - Sort the entries by value
- ArrayObject::ksort() - Sort the entries by key
- ArrayObject::natsort() - Sort entries using a "natural order" algorithm
- ArrayObject::uasort() - Sort the entries with a user-defined comparison function and maintain key association
- ArrayObject::uksort() - Sort the entries by keys using a user-defined comparison function
- natcasesort() - Sort an array using a case insensitive "natural order" algorithm