Easiest way to implode() a two-dimensional array?

Question

I\'m new to PHP, and don\'t have quite the grip on how it works. If I have a two dimensional array as such (returned by a database):

array(3) {   
    [0]=&         


        

Answer 1

function recursive_implode($connector=',', $array=[], $implod='keys'){

    if($implod=='keys'){

        $results=implode($connector,array_keys($array));
    }
    else{

        $results=implode($connector,$array);
    }

    foreach($array as $key=> $value){

        if(is_array($value)){

            $results.=$connector.recursive_implode($connector,$value,$implod);
        }
    }

    return $results;
}

Answer 2

If one simply wants to implode a single array "column" as in this case, then the simplest thing to do is:

implode(",", array_column($array,"tag_id")); 

Answer 3

This modifies your array using array_map, but probably for the better by turning it into a 1D array of tag_id's. Then you can just use implode like normal:

$arr = array_map(function($el){ return $el['tag_id']; }, $arr);
$str = implode(',', $arr);

If you don't want to modify your array than you can just do this:

$str = implode(',', array_map(function($el){ return $el['tag_id']; }, $arr));

Codepad Demo

Answer 4

// simplest
$str = implode(',',array_map('implode',$arr));

Answer 5

One line command

implode(',', array_map('implode', $arr, array_fill(0, count($arr), '')))

Answer 6

You asked for a two-dimensional array, here's a function that will work for multidimensional array.

function implode_r($g, $p) {
    return is_array($p) ?
           implode($g, array_map(__FUNCTION__, array_fill(0, count($p), $g), $p)) : 
           $p;
}

I can flatten an array structure like so:

$multidimensional_array = array(
    'This',
    array(
        'is',
        array(
            'a',
            'test'
        ),
        array(
            'for',
            'multidimensional',
            array(
                'array'
            )
        )
    )
);

echo implode_r(',', $multidimensional_array);

The results is:

This,is,a,test,for,multidimensional,array