PHP: how to perform htmlspecialchar() on an array-of-arrays?

Question

How do I run the PHP function htmlspecialchars() on an array of array objects?

I have the following code:

$result_set = Array
(
    [0] => Array
        (
            [home_id] => 1
            [address] => 4225 Nasmyth Dr
            [city] => Plano
            [state] => TX
            [zip] => 76798
        )

    [1] => Array
        (
            [home_id] => 8
            [address] => 4229 Nasmyth Dr
            [city] => Plano
            [state] => TX
            [zip] => 75093
        )
);

// this doesn't work since $result_set is an array of arrays and htmlspecialchars is expecting a string
htmlspecialchars($result_set, ENT_QUOTES, 'UTF-8')); 

---

UPDATE:

Please note that even though there are quite a few answers below, none of them work for an array-of-arrays. The answers below only work for simple arrays.

I've tried the following, but it doesn't work:

array_walk_recursive($result_set, "htmlspecialchars", array(ENT_QUOTES,'UTF-8'))

I get the following error: htmlspecialchars() expects parameter 2 to be long, string given

---

UPDATE 2

When I try:

function cleanOutput(&$value) {
    return htmlspecialchars($value, ENT_QUOTES, 'UTF-8');
}
print_r($result_set);
print('-------');
print_r(array_walk_recursive($result_set, "cleanOutput"));

I get the following, undesired, output:

Array
(
    [0] => Array
        (
            [home_id] => 1
            [address] => 4225 Nasmyth Dr
            [city] => Plano
            [state] => TX
            [zip] => 76798
        )
    [1] => Array
        (
            [home_id] => 8
            [address] => 4229 Nasmyth Dr
            [city] => Plano
            [state] => TX
            [zip] => 75093
        )
)
-------1

---

UPDATE 3

When I try:

function cleanOutput(&$value) {
    return htmlspecialchars($value, ENT_QUOTES, 'UTF-8');
}
$result_set = Array
    (
        [0] => Array
            (
                [home_id] => 1
                [address] => 4225 Nasmyth Dr
                [city] => Plano
                [state] => TX
                [zip] => 76798
            )

        [1] => Array
            (
                [home_id] => 8
                [address] => 4229 Nasmyth Dr
                [city] => Plano
                [state] => TX
                [zip] => 75093
            )
    );

$cleanedOutput = array();
foreach ($result_set as $rs) {
    $cleaned[] = array_map("cleanOutput", $rs);
}
print_r($cleanedOutput);

I get the following, undesired, results:

{'homes' : []}

Answer 1

You can use array_map() to run that method on each entry.

$cleaned = array_map("htmlspecialchars", $myArray);

If you need to pass arguments to htmlspecialchars(), you can substitute it for your own custom function:

function myFunc($a) {
  return htmlspecialchars($a, ENT_QUOES);
}

$cleaned = array_map("myFunc", $myArray);

Considering the fact that you're dealing with an array of arrays, and not an array of strings, you would need to cycle through the outer-array to get to your strings:

$cleaned = array();
foreach ($result_set as $rs) {
  foreach ($rs as $r) {
    $cleaned[] = array_map("htmlspecialchars", $r);
  }
}

Or, you could use array_walk_recursive():

array_walk_recursive($myArray, "htmlspecialchars");

Note that this method changes the $myArray object by reference, so there's no need to assign the output to a new variable.

Answer 2

You may wish to use array_map as Jonathon Sampson suggested, another alternative is array_walk

The difference is that array_map returns a copy of the array with the function applied to each element, while array_walk operates directly on the array you supply.

Answer 3

If you want to use array_map and pass the function arguments, you can create your own function and use that as the callback:

 function cleanhtml($dirtyhtml) {
       return htmlspecialchars($dirtyhtml, UTF-8);
  }

  $cleaned = array_map("cleanhtml", $myArray);

Answer 4

You don't need to create your own function if you are passing multiple arguments to the called back function.

According to php.net:

array array_map ( callback $callback , array $arr1 [, array $... ] )

So that means if you want to pass multiple arguments you should just pass:

$clean_array = array_map("htmlspecialchars", $myArray, array(ENT_QUOTES, 'UTF-8'));

but for some reason this doesn't work for me.

But this seems to does, don't ask me why.

$clean_array = array_map("htmlspecialchars", $myArray, array(ENT_QUOTES), array('UTF-8'));

Answer 5

function filter(&$value) {
  $value = htmlspecialchars($value, ENT_QUOTES, 'UTF-8');
}
array_walk_recursive($result_set, "filter");
print_r($result_set);

Answer 6

check this http://jvk-codex.blogspot.com/2009/05/php-htmlspecialchars-on-array.html