PHP Array Exercises : Filter array elements with certain key-names

PHP Array: Exercise-51 with Solution

Write a PHP program to filter out some array elements with certain key-names.

Sample Solution:

PHP Code:

$first_array = array('c1' => 'Red', 'c2' => 'Green', 'c3' => 'White', 'c4' => 'Black'); 
$second_array = array('c2', 'c4');
$result = array_diff_key( $first_array, array_flip( $second_array));

Sample Output:

    [c1] => Red                                             
    [c3] => White                                           


Flowchart: PHP - Filter out some elements with certain key-names

PHP Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a PHP script to get the last value of an array without affecting the pointer.
Next: Write a PHP function to filter a multi-dimensional array. The function will return those items that will match with the specified value.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

Follow us on Facebook and Twitter for latest update.

PHP: Tips of the Day

PHP: Where does PHP store the error log? (php5, apache, fastcgi, cpanel)

PHP stores error logs in /var/log/apache2 if PHP is an apache2 module. Shared hosts are often storing log files in your root directory /log subfolder. But...if you have access to a php.ini file you can do this:

error_log = /var/log/php-scripts.log

According to rinogo's comment: If you're using cPanel, the master log file you're probably looking for is stored (by default) at


If all else fails you can check the location of the log file using

<?php phpinfo(); ?>

Ref : https://bit.ly/2EffgH5


We are closing our Disqus commenting system for some maintenanace issues. You may write to us at reach[at]yahoo[dot]com or visit us at Facebook