在PHP中将一个数组分成3个不同的数组

Question

I have an array like this:

array(
    '1' => 'Item 1',
    '2' => 'Item 2',
    '3' => 'Item 3',
    '4' => 'Item 4',
    '5' => 'Item 5',
    '6' => 'Item 6',
    '7' => 'Item 7',
    '8' => 'Item 8',
    '9' => 'Item 9'
);

I want to separate this into 3 arrays where keys 1,2,3 go into $array1,$array2,$array3 respectively and then keys 4,5,6 and then 7,8,9 go into $array1,$array2,$array3 respectively too.

So, the final output would be:

$array1 = array(
    '1' => 'Item 1',
    '2' => 'Item 4',
    '3' => 'Item 7'
);

$array2 = array(
    '1' => 'Item 2',
    '2' => 'Item 5',
    '3' => 'Item 8'
);

$array3 = array(
    '1' => 'Item 3',
    '2' => 'Item 6',
    '3' => 'Item 9'
);

Or, if they keys are preserved (and not 1,2,3 in each array as in my example) then that wouldn't matter either. Either way is fine.

Answer 1

Sth like

$i=0;
foreach($array as $k=>$v) {
 ${"array".$i%3+1}[$k]=$v;
 $i++;
}

Answer 2

foreach($arr as $key => $value) {
    $final_arr[$key % 3][] = $value;
}

Answer 3

for($i = 0; $i < count($input); $i += 3) {
    ${"array".$i} = array_slice($input, 0 + $i, 3);
}

This will split your array into new array on every third element. You can also replace 3 with a variable to split on some other number.

Edit: oh I just noticed, you might want to offset $i to get the array names in correct order. Now it will be array3, array6, array9 etc

Answer 4

   Try This

          $first_arr = array();
                $second_arr = array();
                $third_arr = array();
                $first = 0;
                $second = 1;
                $third = 2;    
                foreach($array as $value)
                {
                    if ($first++ % 3 == 0)
                    $first_arr[] = $value;
                    if ($second++ % 3 == 0)
                    $second_arr[] = $value;
                    if ($third++ % 3 == 0)
                    $third_arr[] = $value;
                }