Iteration through arrays in arrays PHP

Question

Hello

How can i itarate this array

array(2) {
  [0]=>
  array(1) {
    [0]=>
    array(14) {
      [0]=>
      string(17) "ratosk8@censored"
      [1]=>
      string(23) "alokkumar.censored"
      [2]=>
      string(24) "uuleticialima1@censored"
      [3]=>
      string(23) "camera.clicks@censored"
      [4]=>
      string(24) "billthailand@censored"
      [5]=>
      string(17) "v.golev@censored"
      [6]=>
      string(22) "flipe.lost@censored"
      [7]=>
      string(25) "notherdirtybird@censored"
      [8]=>
      string(21) "booktiphani@censored"
      [9]=>
      string(32) "opinion?jazzantoledo@censored"
      [10]=>
      string(25) "skateforemerica@censored"
      [11]=>
      string(28) "blockdymezmagazine@censored"
      [12]=>
      string(17) "and6451@censored"
      [13]=>
      string(22) "flipe.lost@censored"
    }
  }
  [1]=>
  array(1) {
    [0]=>
    array(14) {
      [0]=>
      string(17) "ratosk8@censored"
      [1]=>
      string(23) "alokkumar.jsr@censored"
      [2]=>
      string(24) "[email protected]"
      [3]=>
      string(23) "[email protected]"
      [4]=>
      string(24) "[email protected]"
      [5]=>
      string(17) "[email protected]"
      [6]=>
      string(22) "[email protected]"
      [7]=>
      string(25) "[email protected]"
      [8]=>
      string(21) "[email protected]"
      [9]=>
      string(32) "[email protected]"
      [10]=>
      string(25) "[email protected]"
      [11]=>
      string(28) "[email protected]"
      [12]=>
      string(17) "[email protected]"
      [13]=>
      string(22) "[email protected]"
    }
  }
}

Answer 1

You could use a foreach inside another foreach:

foreach ($array as $item) {
    foreach ($item[0] as $email) {
        // …
    }
}

Note that I used $item[0] instead of just $item.

You could also use a function to flatten that multidimensional array and then ireate it with a single foreach:

function array_flatten($array) {
    if (!is_array($array)) {
        return false;
    }
    $result = array();
    $stack = $array;
    $len = count($stack);
    while ($len) {
        $val = array_shift($stack);
        --$len;
        if (is_array($val)) {
            foreach ($val as $key => $val) {
                if (is_array($val)) {
                    array_unshift($stack, $val);
                    ++$len;
                } else {
                    $result[] = $val;
                }
            }
        } else {
            $result[] = $val;
        }
    }
    return $result;
}

Answer 2

Well, what you have here is a two-element array, where each element contains a one-element array, that contains the arrays you want to iterate over.

// This gets us the two seperate arrays
foreach ($root_array as $2nd_level_array) {

  // But now, we still have one more one-element array in each...
  // we could iterate, but since there's only one element, 
  // we can just grab that element using array_pop()
  $email_address_array = array_pop($2nd_level_array)

  // now we can iterate over each of the two lists
  foreach ($email_address_array as $email_address) {

    // process email address

  }

}

Answer 3

Maybe a bit more flexible solution is Recursion:

<?php

$a = array();
$a[] = array( array( "a", "b") );
$a[] = array( array( array("c", "d"), array("e", "f"), array("g", "h")));


print_arr($a);

function print_arr($obj) {
    foreach($obj as $k => $v) {
     if(is_array($v)) {
      print_arr($v);
     }else{
      echo $v ."<br />";
     }
    }
}

Useless fact: my first recursive function that doesn't have a stop condition but a go condition.

Answer 4

The question is not too specific about how to iterate the array, and since it's a multidimensional array there are several ways to do it.

Below i outline the two ways i see would make the most sense to me.

First off i travel through the array listing items sequential.

In my second attempt i travel through the array grouping the second level items according to key.

$a = array(
    0 => array(
    0 => array(
        0 => "test0-0-0",
        1 => "test0-0-1"
    )
    ),
    1 => array(
    0 => array(
        0 => "test1-0-0",
        1 => "test1-0-1"
    )
    )
);

echo "Method 1\n";
foreach ($a as $array) {
    foreach ($array[0] as $item) {
    echo "$item\n";
    }
}
echo "Method 2\n";
$a0 = $a[0][0];
$a1 = $a[1][0];
if (count($a0) == count($a1)) {
    for ($i=0;$i<count($a0);++$i) {
    echo $a0[$i]."\n";
    echo $a1[$i]."\n";
    }
}

Answer 5

I would create a function and pass it into array_walk_recursive

function spam_someone($value, $key)
{
    $email=$value;
    send_evil_spam($email);
 }

 array_walk_recursive($people_to_spam, 'spam_someone');

Alternatively, you could use a RecursiveIteratorIterator to iterate sequentially over a RecursiveArrayIterator. They're poorly documented, but I believe the code would look like this:

//iterate over the array using recursion as in les' answer (doesn't gain much)
$array_iter=new RecursiveArrayIterator($people_to_spam);

//Ahh, here we go, this will let us iterate over the leaves in a sequential manner
$iter_iter=new RecursiveIteratorIterator($array_iter);
foreach($iter_iter as $email)
{
    send_evil_spam($email)
}

I find these two solutions to be the cleanest and most readable. If the array is only ever going to be 3 levels deep though, I might just hard code that. If I didn't know about either of these, I would just write my own recursive function to do it (as in les' answer).