Passing a variable to a lambda-function

Question

How to pass a variable "$field" to a lambda-function?

function implode_assoc_array($array, $field)
{
    // $ids = array_column($array, $field); PHP 5.5!
    $ids = array_map(function($item) { return $item[$field]; }, $array);
    return implode(', ', $ids);
}

implode_assoc_array($my_multidimensional_array, 'id');

Message: Undefined variable: field

score 5 · Accepted Answer · answered Sep 27 '13 at 14:42

5

try

array_map(function($item) use($field) { return $item[$field]; }, $array);

see the example http://php.net/manual/en/functions.anonymous.php

answered Sep 27 '13 at 14:42

egig

4,370
5
29
50

u'r welcome, glad can help :) – egig Sep 27 '13 at 14:58

score 0 · Answer 2 · answered Sep 27 '13 at 14:46

function implode_assoc_array($array, $field)
{
    // $ids = array_column($array, $field); PHP 5.5!
    $ids = array_map(function($item) use ($field) { return $item[$field]; }, $array);
    return implode(', ', $ids);
}

implode_assoc_array($my_multidimensional_array, 'id');

If you want to modify the variable use

    $ids = array_map(function($item) use (&$field) { return $item[$field]; }, $array);

See PHP manual page, Example #3 Closures and scoping

Passing a variable to a lambda-function

2 Answers2