PHP Array Exercises : Delete a specific value from an array using array_filter() function

Last update on May 30 2022 11:41:58 (UTC/GMT +8 hours)

PHP Array: Exercise-53 with Solution

Write a PHP script to delete a specific value from an array using array_filter() function.

Sample Solution:

PHP Code:

<?php
 $colors = array('key1' => 'Red', 'key2' => 'Green', 'key3' => 'Black');
$given_value = 'Black';
print_r($colors);

$new_filtered_array = array_filter($colors, function ($element) use ($given_value) { return ($element != $given_value);}); 
print_r($filtered_array);
  
print_r($new_filtered_array);
?>

Sample Output:

Array                                                       
(                                                           
    [key1] => Red                                           
    [key2] => Green                                         
    [key3] => Black                                         
)                                                           
PHP Notice:  Undefined variable: filtered_array in /home/stu
dents/2f6e9db0-f423-11e6-a8c0-b738b9ff32f9.php on line 7    
Array                                                       
(                                                           
    [key1] => Red                                           
    [key2] => Green                                         
)

Flowchart:

PHP Code Editor:

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Previous: Write a PHP function to filter a multi-dimensional array. The function will return those items that will match with the specified value.
Next: Write a PHP script to remove all white spaces in an array.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC