对数组重复值进行排序并使其成为关键

I'm having trouble getting to re-arrange an array by the key's duplicate values of the Key 'Company' and making it the value so that it is re-arranged in the code below this one:

Original array:

$array = array(
    'number' => 2,
    'items' => 
        array(
            'Company' => 'ABC',
            'First' => 'John',
            'Last' => 'Doe',
        ),
        array(
            'Company' => 'ABC',
            'First' => 'Jane',
            'Last' => 'Doe',
        ),
        array(
            'Company' => 'XYZ',
            'First' => 'Peter',
            'Last' => 'Pumpkin',
        ),
);

I want to re-sort the array on the 'Company' value and make it the key, like the example below:

$array = array(
    'number' => 2,
    'items' => 
        array(
            'ABC' => 
                array(
                'First' => 'John',
                'Last' => 'Doe'),
                array(
                'First' => 'Jane',
                'Last' => 'Doe'),
            'XYZ' => 
                array(
                'First' => 'Peter',
                'Last' => 'Pumpkin'),
        )
);

I looked hard in the PHP Docs, so this seems to be a unique type of sort.

$array = array(
    'number' => 2,
    'items' => array(
        array(
            'Company' => 'ABC',
            'First' => 'John',
            'Last' => 'Doe',
        ),
        array(
            'Company' => 'ABC',
            'First' => 'Jane',
            'Last' => 'Doe',
        ),
        array(
            'Company' => 'XYZ',
            'First' => 'Peter',
            'Last' => 'Pumpkin',
        )
    )
);

$final = $array;
$final['items'] = array();
foreach ($array['items'] as $item) {
    $final['items'][$item['Company']] = $item;
    unset($final['items'][$item['Company']]['Company']);
}

var_dump($final);

Result:

array (size=2)
  'number' => int 2
  'items' => 
    array (size=2)
      'ABC' => 
        array (size=2)
          'First' => string 'Jane' (length=4)
          'Last' => string 'Doe' (length=3)
      'XYZ' => 
        array (size=2)
          'First' => string 'Peter' (length=5)
          'Last' => string 'Pumpkin' (length=7)

You can construct the array you want by looping over your original array.

BTW, I think you meant to put another array() to hold all the items in.

$array = array(
        'number' => 2,
        'items' =>
        array(//I assume this was missing in your original Question
        array(
                'Company' => 'ABC',
                'First' => 'John',
                'Last' => 'Doe',
        ),
        array(
                'Company' => 'ABC',
                'First' => 'Jane',
                'Last' => 'Doe',
        ),
        array(
                'Company' => 'XYZ',
                'First' => 'Peter',
                'Last' => 'Pumpkin',
        ),
        )
);

$newarray = array();

foreach ($array['items'] as $key=>$val){
    $company = $val['Company'];
    if (empty($newarray[$company])){
        //set a new key to hold our data
        $newarray[$company] = array();
    }
    // because $val contains 'Company', we want to get rid of it
    unset($val['Company']);
    // add the current item under the company key
    $newarray[$company][] = $val;

}

$array['items'] = $newarray;
print_r($array);

I see CodeGodie just answered with a much shorter version of this. :)