Question

I have the following array of client data:

Array
(
    [0] => Array
        (
            [client_id] => 3680
            [firstname] => Brian
            [surname] => May
            [company] => 
        )

    [1] => Array
        (
            [client_id] => 3688
            [firstname] => Freddie
            [surname] => Mercury
            [company] => 
        )

    [2] => Array
        (
            [client_id] => 3694
            [firstname] => Roger
            [surname] => Taylor
            [company] => 
        )
)

I want to display this in a table however if any element is null in ALL cases (such as “company” in this example) I don’t want to show that column in the table.

Can anyone suggest how this may be done without first looping through the whole array?

Answer 1

You cant avoid doing loopings in this case, so the best approach I can think about your case is:

<?php

$test = array
            (
        array
        (
            client_id => 3680,
            firstname => 'Brian',
            surname => 'May',
            company => null
        ),

        array
        (
            client_id => 3688,
            firstname => 'FreddieFreddie',
            surname => 'Mercury',
            company => null
        ),

        array
        (
            client_id => 3694,
            firstname => 'Roger',
            surname => 'Taylor',
            company => null
        )
);

$empty_columns = false;
foreach ($test as $item) {
    $keys = array_keys($item, null, true);

    if (count($keys) == 0)
    {
        $empty_columns = null;
        break;
    }

    if ($empty_columns===false)
        $empty_columns = $keys;

    $empty_columns= array_intersect($empty_columns, $keys); 
}
print_r($empty_columns);        
?>

The $empty_columns will return one array with the columns where all the values are NULL;
In this example:

Array
(
    [0] => company
)

Just check this array before print your columns.