在php中访问0索引xml属性

I have written a program which read an XML file and provide me an array. So I further perform my operations but I am not able to get the value of 0 index.

$xml = simplexml_load_file("app_string.xml");

foreach ($xml as $value) {
    echo "<pre>";
    print_r($value);
}

That is the output:

SimpleXMLElement Object (
    [@attributes] => Array
        (
            [name] => app_name
        )

    [0] => My Data )

I tried with

$value->{0} 

and

$value['0']

Not getting the desire data.

How can I get My Data from [0] => My Data

To retrieve the element data, you can simple cast the XML element to a string, as in:

$xml = simplexml_load_file("app_string.xml");

foreach ($xml as $value) {
    echo "<pre>";
    $data = (string)$value;
    echo $data;
}