I've found a lot of information on joining arrays together using array_merge, but I'm wondering how easy it is to merge multiple arrays in order of their value index, rather than simply joining them together.
For example, if we had the following three arrays:
$a = array('One','Two','Three','Four');
$b = array(1,2,3,4);
$c = array('i','ii','iii','iv');
Could we merge them into?:
One,1,i,Two,2,ii,Three,3,iii,Four,4,iv
Instead of:
One, Two, Three, Four, 1, 2, 3, 4, i, ii, iii, iv
you can write your custom function like this.
$a = array('One','Two','Three','Four');
$b = array(1,2,3,4);
$c = array('i','ii','iii','iv');
$count = max(count($a), count($b), count($c));
$newarray = array();
for($i=0; $i < $count; $i++) {
if (isset($a[$i])) $newarray[] = $a[$i];
if (isset($b[$i])) $newarray[] = $b[$i];
if (isset($c[$i])) $newarray[] = $c[$i];
}
var_dump($newarray);
$count = max(count($a), count($b), count($c)); and then do an isset() on each array before attempting to add an index to $newarray
I wouldn't actually use this code due to readability, but it's cool that it works.
Make an array of arrays first
$a = array('One','Two','Three','Four');
$b = array(1,2,3,4);
$c = array('i','ii','iii','iv');
$arrays = [$a, $b, $c];
then
array_unshift($arrays, null);
$n = call_user_func_array('array_merge', call_user_func_array('array_map', $arrays));
print_r($n);
yields
Array
(
[0] => One
[1] => 1
[2] => i
[3] => Two
[4] => 2
[5] => ii
[6] => Three
[7] => 3
[8] => iii
[9] => Four
[10] => 4
[11] => iv
)
demo http://codepad.org/FdZKffPQ
it makes use of this matrix transpose method https://stackoverflow.com/a/3423692
forloop.