CODEWITHSUNDEEP
phparrays
EmmyS
EmmyS

Reputation: 12138

count() not returning correct number of array elements

I have two arrays (records returned from a database query) that I'm merging. I then need to get a count of the elements in the combined array.

Here are the print_r results of the two original arrays:

Array(
    [0] => stdClass Object([id] => 25590)
    [1] => stdClass Object([id] => 40657)
    [2] => stdClass Object([id] => 60685)
    [3] => stdClass Object([id] => 61900)
    [4] => stdClass Object([id] => 65224)
)

Array(
    [0] => stdClass Object([id] => 88406)
)

Merged array created like this:

$licensed_users = array_unique(array_merge($lu, $lu2));

And the results of the merge (in this case there weren't any duplicates, but there could be, hence the array_unique) 

Array(
    [0] => stdClass Object([id] => 25590)
    [1] => stdClass Object([id] => 40657)
    [2] => stdClass Object([id] => 60685)
    [3] => stdClass Object([id] => 61900)
    [4] => stdClass Object([id] => 65224)
    [5] => stdClass Object([id] => 88406)
)

The array is assigned to a session variable, to be used on another page:

    $_SESSION['licensed_users'] = $licensed_users;

I now want to know how many elements are in the merged array via the session variable.

count($_SESSION['licensed_users'])

I would expect this to return 6. Instead, it returns 1. Any idea why?

EDITED TO ADD CODE FOR @SURREALDREAMS

$_SESSION['licensed_users'] = array_unique(array_merge($lu, $lu2));
print_r($lu);
print_r($lu2);
print_r($_SESSION['licensed_users']);
echo "there are ". count($_SESSION['licensed_users']) . " licensed users";

This code returns the following:

$lu Array(
    [0] => stdClass Object([id] => 25590)
    [1] => stdClass Object([id] => 40657)
    [2] => stdClass Object([id] => 60685)
    [3] => stdClass Object([id] => 61900)
    [4] => stdClass Object([id] => 65224)
)

$lu2 Array(
    [0] => stdClass Object([id] => 88406)
)

$_SESSION['licensed_users'] Array(
    [0] => stdClass Object([id] => 25590)
)

The echo line returns 1.

If I try it the other way you suggested:

$licensed_users = array_unique(array_merge($lu, $lu2));
$_SESSION['licensed_users'] = $licensed_users;
echo "there are ". count($_SESSION['licensed_users'], COUNT_RECURSIVE) -1 . " licensed users";

the arrays returned have the same contents, but the echo line returns -1.

Upvotes: 3

Views: 904

Answers (3)

Frank
Frank

Reputation: 459

<?
$my_array = array(0 => 1, 1 => 2, 2 => 3, 3 => 4, 4 => 5);

$your_array = array(0 => 1, 1 => 2);

$the_array = array_unique(array_merge($my_array, $your_array)); 

$_SESSION['test'] = $the_array;

print_r($the_array);

echo(count($_SESSION['test']));
?>

yields:

Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 ) 5

<?
$my_array = array(0 => 1, 1 => 1, 2 => 1, 3 => 1, 4 => 1);

$your_array = array(0 => 1, 1 => 1);

$the_array = array_unique(array_merge($my_array, $your_array)); 

$_SESSION['test'] = $the_array;

print_r($the_array);

echo(count($_SESSION['test']));
?>

yields:

Array ( [0] => 1 ) 1

my guess would be your stdClass Object([id] => xxxxx) are all the same...

EDIT

another test:

<?
$my_array = array(0 => array('id' => 11), 1 => array('id' => 22), 
                  2 => array('id' => 22), 3 => array('id' => 33), 4 => array('id' => 445));

$your_array = array(0 => array('id' => 11), 1 => array('id' => 7908));

$the_array = array_unique(array_merge($my_array, $your_array), SORT_REGULAR); 

$_SESSION['test'] = $the_array;

print_r($the_array);

echo(count($_SESSION['test']));
?>

yields:

Array ( [0] => Array ( [id] => 11 ) [1] => Array ( [id] => 22 ) [3] => Array ( [id] => 33 ) [4] => Array ( [id] => 445 ) [6] => Array ( [id] => 7908 ) ) 5

I think this is what you're looking for.

Upvotes: 0

Mr. Llama
Mr. Llama

Reputation: 20899

The issue is in the array_unique() call. From the documentation: 

Two elements are considered equal if and only if (string) $elem1 === (string) $elem2. In words: when the string representation is the same.

Those objects are being converted to strings before being compared. You may have to manually prune them based on some other property.

Upvotes: 0

Surreal Dreams
Surreal Dreams

Reputation: 26380

It's counting the contents of $_SESSION['licensed_users'], which is 1 - your $licensed_users array. You could instead try:

count($_SESSION['licensed_users'], COUNT_RECURSIVE);

This will return 7. You could approach this knowing your structure and use:

count($_SESSION['licensed_users'], COUNT_RECURSIVE) -1;

Which returns the expected 6.

To simplify a bit more, consider this:

$_SESSION['licensed_users'] = array_unique(array_merge($lu, $lu2));

Then count($_SESSION['licensed_users']; should return 6.

Upvotes: 1

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