How to remove empty associative array entries

问题:

I have an associative array: $csv_arr

Array
(
    [0] => Array
        (
            [Enfalac] => alpha linolenic acid 300 mg
            [Enfapro] => alpha linolenic acid 200 mg
        )

    [1] => Array
        (
            [Enfalac] => arachidonic acid 170 mg
            [Enfapro] => 
        )

    [2] => Array
        (
            [Enfalac] => 
            [Enfapro] => 
        )

    [3] => Array
        (
            [Enfalac] => calcium 410 mg
            [Enfapro] => calcium 550 mg
        )
)

How can I remove all completely empty entries such as $csv_arr[2] but preserve partial entries such as $csv_arr[1]

I've tried $csv_arr = array_filter(array_map('array_filter', $csv_arr)); but this removes the empty element: $csv_arr[1]['Enfapro']

Thx

回答1:

Try this, a little weird, but :

array_filter($csv_arr, function($v){return array_filter($v) == array();});

Completely untested and I don't remember if this is the proper syntax or not for closures, but it could work.

Edit (tested and working):

<?php
$csv_arr = array(
    0 => array(
            'Enfalac' => 'alpha linolenic acid 300 mg',
            'Enfapro' => 'alpha linolenic acid 200 mg'
        ),

    1 =>  array(
            'Enfalac' => 'arachidonic acid 170 mg',
            'Enfapro' => ''
        ),

    2 =>  array(
            'Enfalac' => '',
            'Enfapro' => ''
        ),

    3 =>  array(

            'Enfalac' => 'calcium 410 mg',
            'Enfapro' => 'calcium 550 mg'
        )
);
$c = function($v){
    return array_filter($v) != array();
};
var_dump(array_filter($csv_arr, $c));
?>

回答2:

OK, thanks for the help everyone. I managed to do it like this in a loop.

if(implode('',$csv_arr[$i])==''){
    unset($csv_arr[$i]);
}

回答3:

I think this is the better and appropriate solution for this,

here is the code:

$arr[0]['id'] = "id1";
$arr[0]['name'] = "testing";
$arr[1]['id'] = "id2";
$arr[1]['name'] = "another";
$arr[2]['id'] = "";
$arr[2]['name'] = "";
$d = array_keys($arr);
foreach($arr as $key=>$values){
    $a = array_keys($values);
    $n = count($a);
    for($i=0,$count=0;$i<$n;$i++){
        if($values[$a[$i]]==NULL){
            $count++;
        }
    }
    if($count==$n){

        unset($arr[$key]);
    }
}
echo "<pre>";
print_r($arr);

If you want this to work for more nested associative arrays, you can implement same in recursive function.

Thanks, Nirav