sort an array by an index preset - php

Question

i have this array
$immagini = array('1.jpg','2.jpg','3.jpg','4.jpg');
if i make var_dump($immagini) return this
array(4) {
[0]=> string(5) "1.jpg"
[1]=> string(5) "2.jpg"
[2]=> string(5) "3.jpg"
[3]=> string(5) "4.jpg"
}
now how do I order them in another way, i like start from index [2]....so i want this result
array(4) {
[2]=> string(5) "3.jpg"
[3]=> string(5) "4.jpg"
[0]=> string(5) "1.jpg"
[1]=> string(5) "2.jpg"
}
I would like from an index and return the complete list

Answer 1

You can't use var_dump to accomplish that. You'd need your own loop to print from the custom starting index. Start from the starting index and increment your loop iterator by one at each iteration until you have looped length of array times. When you want to access an array element, use loopIterator mod length of array

Answer 2

You could sort them with a comparison function that moves all index < 2 to the end of the list. For example, here would be such a comparison:
function cmp($a,$b) {
$a = ($a < 2) ? $a + 1000 : $a;
$b = ($b < 2) ? $b + 1000 : $b;
return $a - $b;
}
Called like this:
$immagini = array('1.jpg','2.jpg','3.jpg','4.jpg');
uksort($immagini, 'cmp');
var_dump($immagini);
Gives the following output:
array(4) {
[2]=>
string(5) "3.jpg"
[3]=>
string(5) "4.jpg"
[0]=>
string(5) "1.jpg"
[1]=>
string(5) "2.jpg"
}
Demo: http://ideone.com/XeAkQL