PHP将XML输出读取为数组

I'm looping through node values in my XML file, but I can't get the output as I need it. Below is the code that I'm working with.

PHP:

$xml = simplexml_load_file("file.xml") or die("Error: Cannot create object");         
$result = array();
foreach($xml->picture as $item)
{
     $result[]  =  $item->logo;
}

echo '<pre>';
print_r($result);
echo '</pre>';

Current output:

Array
(
    [0] => SimpleXMLElement Object
        (
            [0] => img/a.jpg
        )

    [1] => SimpleXMLElement Object
        (
            [0] => img/b.jpg
        )

    [2] => SimpleXMLElement Object
        (
            [0] => img/c.jpg
        )

    ...
 )

Desired Output:

Array
(
    [0] => a.jpg
    [1] => b.jpg
    [2] => c.jpg

    ...
)

Check this link out: here

function toArray(SimpleXMLElement $xml) {
    $array = (array)$xml;

    foreach ( array_slice($array, 0) as $key => $value ) {
        if ( $value instanceof SimpleXMLElement ) {
            $array[$key] = empty($value) ? NULL : toArray($value);
        }
    }
    return $array;
}

Assign the number of the loop in the array, your code stays like this:

$xml = simplexml_load_file("file.xml") or die("Error: Cannot create object");         
$result = array();
$i = 0;//set a variable to loop throw the foreach
foreach($xml->picture as $item)
    {
//assign the variable with the number of the loop in the disired array
         $result[$i]  =  $item->logo;
    }

echo '<pre>';
print_r($result);
echo '</pre>';