PHP | asort() Function

The asort() function is an inbuilt function in PHP which is used to sort an array according to values. It sorts in a way that relation between indices and values is maintained. By default it sorts in ascending order of values.

Syntax:

bool asort( $array, $sorting_type )

Parameters: This function accepts two parameters as mentioned above and described below:

• $array: This parameter specifies the array which to be sort. It is a mandatory parameter.
• $sorting_type: This is an optional parameter. There are different sorting types which are discussed below:
  • SORT_REGULAR: The value of $sorting_type is SORT_REGULAR then items are compare normally.
  • SORT_NUMERIC: The value of $sorting_type is SORT_NUMERIC then items are compares numerically.
  • SORT_STRING: The value of $sorting_type is SORT_STRING then items are compares as string.
  • SORT_LOCALE_STRING: The value of $sorting_type is SORT_STRING then items are compares as string, based on current locale.

Return Value: This function returns True on success or False on failure.

Below programs illustrate the asort() function in PHP.
Program 1:

<?php
// PHP program to illustrate
// asort() function

// Input different array elements
$arr = array("0" => "Web Technology",
            "1" => "Machine Learning",
            "2" => "GeeksforGeeks",
            "3" => "Computer Graphics",
            "4" => "Videos",
            "5" => "Report Bug",
            "6" => "Article",
            "7" => "Sudo Placement",
            "8" => "SContribute",
            "9" => "Reset",
            "10" => "Copy",
            "11" => "IDE",
            "12" => "Gate Note",
        );

// Implementation of asort()
asort($arr);

// for-Loop for displaying result
foreach ($arr as $key => $val) {
    echo "[$key] = $val";
    echo"\n";
}

?>

Output:

[6] = Article
[3] = Computer Graphics
[10] = Copy
[12] = Gate Note
[2] = GeeksforGeeks
[11] = IDE
[1] = Machine Learning
[5] = Report Bug
[9] = Reset
[8] = SContribute
[7] = Sudo Placement
[4] = Videos
[0] = Web Technology

Program 2:

<?php
// PHP program to illustrate
// asort() function

// Input different array elements
$arr = array("a" => 11,
            "b" => 22,
            "d" => 33,
            "n" => 44,
            "o" => 55,
            "p" => 66,
            "r" => 77,
            "s" => 2,
            "q" => -11,
            "t" => 3,
            "u" => 1000,
            "z" => 1,

        );
// Implementation of asort()
asort($arr);

// for-Loop for displaying result
foreach ($arr as $key => $val) {
    echo "[$key] = $val";
    echo"\n";
}

?>

Output:

[q] = -11
[z] = 1
[s] = 2
[t] = 3
[a] = 11
[b] = 22
[d] = 33
[n] = 44
[o] = 55
[p] = 66
[r] = 77
[u] = 1000

Reference: http://php.net/manual/en/function.asort.php