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PHP

Posted by Kristian Woods
Kristian Woods
23,414 Points

I don't understand the foreach loop in PHP

I have two arrays. I then create a third empty array, which gets populated with the details of the first two. I have it working, but I don't understand why

<?php

$map = array(

    'Title',
    'Name',
    'Lastname',

);

$data = array(
    'Mr',
    'Kristian',
    'Woods',
);


$row = array();
      if (is_array($map) && count($map) > 0 && is_array($data) && count($map) > 0) {
        foreach ($map as $key => $field) {
          $row[$field] = $data[$key]; // I'm confused at this line
        }
      }
?>

So, are you creating a key for '$row' on the first pass through the loop. And that key equals 'Title' on the first pass. 'Name' on the second pass. Then 'Lastname' on the third?

I'm confused at:

<?php
    $row[$field] = $data[$key];
?>

$data[$key] - I thought would be 0, 1, 2 - as you go through the array. But, no, it comes up with 'Mr', 'Kristian', 'Woods' - I thought $key was the index value of that array....????

1 Answer

John Awoyele
John Awoyele
36,212 Points
John Awoyele
John Awoyele
36,212 Points

So $key = 0,1,2 as the loop iterates (goes around),

$data[0] = 'Mr' $data[1] = 'Kristian'

e.t.c.

print_r($data);
Array
(
    [0] => Mr
    [1] => Kristian
    [2] => Woods
)