Remove multidimensional array with empty sub arrays using PHP - php

Question

I have this array as follows. Every student has 7 arrays starting from Monday to Sunday and inner array of each has events for day
$array = [
'Alex' => [
[
['event' => 'eventName1'],['event' => 'eventName2']
],
[
['event' => 'eventName3'],['event' => 'eventName4']
],
[
['event' => 'eventName5'],['event' => 'eventName6']
],
[
['event' => 'eventName7'],['event' => 'eventName8']
],
[],
[],
[]
],
'christoper'=>[
[],[],[],[],[],[],[]
]
];
The output array should be
[
'Alex' => [
[
['event' => 'eventName1'],['event' => 'eventName2']
],
[
['event' => 'eventName3'],['event' => 'eventName4']
],
[
['event' => 'eventName5'],['event' => 'eventName6']
],
[
['event' => 'eventName7'],['event' => 'eventName8']
],
[],
[],
[]
]
];
I have tried this
$array = array_filter(array_map('array_filter', $array));
but the result is vain. Can anyone help me in getting desired output. I want to filter out students with no events

Answer 1

You can do this:
<?php
$output = array_filter($array, function (array $studentDays) {
foreach ($studentDays as $day) {
// if there is a *non-empty* day, we return early and keep the whole record
if (! empty($day)) {
return true;
}
}
// only empty days, so discard the record
return false;
});
https://3v4l.org/AkshS

Answer 2

Loop over array and apply array_filter
$array = [
'Alex' => [
[
['event' => 'eventName1'],['event' => 'eventName2']
],
[
['event' => 'eventName3'],['event' => 'eventName4']
],
[
['event' => 'eventName5'],['event' => 'eventName6']
],
[
['event' => 'eventName7'],['event' => 'eventName8']
],
[],
[],
[]
],
'christoper'=>[
[],[],[],[],[],[],[]
]
];
foreach( $array as $key => $value ){
$array[$key] = array_filter($value);
}
print_r( $array );

Answer 3

A recursive call to array_filter will do the job; in the outer call we check the size of the returned array to decide whether to keep that element or not (it will be 0 if the array consisted solely of empty arrays, as it does for 'christopher'):
$array = array_filter($array, function ($v) { return count(array_filter($v)); });
Demo on 3v4l.org