Access array element indexed by numerical string

Question

I have encountered something odd.

I have a php array, indexed with numerical keys. However it appears impossible to access any of the elements because php automatica

Answer 1

String keys containing valid integer values would be cast to integer keys automatically in “normal” array creation – but it seems casting from object to array doesn’t apply the same logic.

It can be fixed however, by using

$array = array_combine(array_keys($array), array_values($array));

after your line that creates the array from the object. http://codepad.viper-7.com/v5rGJa

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Although, same as Dave already said in his comment, using get_object_vars looks like a “cleaner” solution to me as well.

Answer 2

foreach ($array as $key => $value){
    var_dump($key);
    var_dump($value);
}

shows

string(1) "1"
string(3) "one"

But echo $array['"1"']; gives

E_NOTICE :  type 8 -- Undefined index: "1" -- at line 8

That's strange!

Answer 3

Unbelievable but this is normal behavior in php, it was considered as a bug (link) in the year 2008.

But they just pointed out to the manual for the cast with (array):

If an object is converted to an array, the result is an array whose elements are the object's properties. The keys are the member variable names, with a few notable exceptions: integer properties are unaccessible;

You can use get_object_vars() instead:

$object = new stdClass();
$object->{'1'} = 'one';

$array = get_object_vars( $object );

$key = '1';
echo $array[1]."<br>";
echo $array['1']."<br>";
echo $array["1"]."<br>";
echo $array[(string)1]."<br>";
echo $array[$key]."<br>";

Doesn't explain why this happens, but is a solution to avoid the cast problem.

Off topic but I thought maybe it is interesting. Found this in the manual.

To avoid these kind of problems, always use an integer OR a string as index, don't mix it up and don't use integers in a string.

Example of mixed array:

$array = array(
    1    => "a",
    "1"  => "b",//overrides 1
    1.5  => "c",//overrides "1"
    true => "d",//overrides 1.5
);

var_dump($array);

Answer 4

You can use

$vars  = get_object_vars($object);
echo $vars[1];