Alternate to array_column() - php

Question

I have used array_column() in a project, and after uploading I found out that only PHP 5.5 or above support this function, and I think the hosting I use don't support PHP 5.5 or above.
So I want to know if is there any alternate to fix this error?
This is how I am using array_count in my project:
array_count_values(array_column(json_decode(json_encode($queryResultArray), true), $idForBar));
This is working fine in my local xampp and wampp also, but on server it is giving issue. Looking any alternate function or solution.

Answer 1

Add your own function array_column if you PHP version does not support it:
<?php
if (! function_exists('array_column')) {
function array_column(array $input, $columnKey, $indexKey = null) {
$array = array();
foreach ($input as $value) {
if ( !array_key_exists($columnKey, $value)) {
trigger_error("Key \"$columnKey\" does not exist in array");
return false;
}
if (is_null($indexKey)) {
$array[] = $value[$columnKey];
}
else {
if ( !array_key_exists($indexKey, $value)) {
trigger_error("Key \"$indexKey\" does not exist in array");
return false;
}
if ( ! is_scalar($value[$indexKey])) {
trigger_error("Key \"$indexKey\" does not contain scalar value");
return false;
}
$array[$value[$indexKey]] = $value[$columnKey];
}
}
return $array;
}
}
Reference:

Answer 2

You can also use array_map() function if you haven't array_column() because of PHP<5.5:
Example:
$a = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
)
);
array_column($a, 'last_name');
Becomes:
array_map(function($element) {
return $element['last_name'];
}, $a);
So it your case the code will be:
array_count_values(
array_map(function($arr) use ($idForBar) {
return $arr[$idForBar];
}, $queryResultArray)
);
This above is working on PHP 5.3.0 and above!
If you have < PHP 5.3.0, as you wrote PHP 5.2.17, just use simple function:
function get_field_data($array, $field, $idField = null) {
$_out = array();
if (is_array($array)) {
if ($idField == null) {
foreach ($array as $value) {
$_out[] = $value[$field];
}
}
else {
foreach ($array as $value) {
$_out[$value[$idField]] = $value[$field];
}
}
return $_out;
}
else {
return false;
}
}
And the usage:
$output = get_field_data($queryResultArray, $idForBar);

Answer 3

You can also use the alternative code of array_column(), it's simple just paste below line and replace your variable.
Code:
array_map(function($element){return $element['last_name'];}, $a);

Answer 4

Using array_map() instead, something like:
array_count_values(
array_map(
function($value) use ($idForBar) {
return $value[$idForBar];
},
json_decode(
json_encode($queryResultArray),
true
)
)
);

Answer 5

You can always use another implementation of function array_column
if (!function_exists('array_column')) {
function array_column(array $array, $columnKey, $indexKey = null)
{
$result = array();
foreach ($array as $subArray) {
if (!is_array($subArray)) {
continue;
} elseif (is_null($indexKey) && array_key_exists($columnKey, $subArray)) {
$result[] = $subArray[$columnKey];
} elseif (array_key_exists($indexKey, $subArray)) {
if (is_null($columnKey)) {
$result[$subArray[$indexKey]] = $subArray;
} elseif (array_key_exists($columnKey, $subArray)) {
$result[$subArray[$indexKey]] = $subArray[$columnKey];
}
}
}
return $result;
}
}

Answer 6

There is an official recommendation for PHP versions that don't support array_colum() under the "see also" section:
» Recommended userland implementation for PHP lower than 5.5
Their recommendation is another if (!function_exists('array_column')) approach, but the code is actually extracted from the array_column library and is a little more generalized than the examples on this page.