PHP: Count function with an associative array

Question

How does the count function work with arrays, like the one below?

My thought would be that the following code outputs 4, because there are four elements there:

$a = array
(
 "1" => "A",
 1 => "B",
 "C",
 2 => "D"
);
echo count($a);

• Peter Mortensen: Where is the code example from? It is similar to example #2, "Type casting and overwriting example" (my emphasis), in Arrays (official documentation).
• Peter Mortensen: The title ought to be more specific. For example, some answerers don't read past the title...

Answer 1

count works exactly as you would expect, e.g., it counts all the elements in an array (or object). But your assumption about the array containing four elements is wrong:

• "1" is equal to 1, so 1 => "B" will overwrite "1" => "A".
• because you defined 1, the next numeric index will be 2, e.g. "C" is 2 => "C"
• when you assigned 2 => "D" you overwrote "C".

So your array will only contain 1 => "B" and 2 => "D" and that's why count gives 2. You can verify this is true by doing print_r($a). This will give

Array
(
 [1] => B
 [2] => D
)

Please go through Arrays again.

Answer 2

You can use this example to understand how count works with recursive arrays

<?php
$food = array('fruits' => array('orange', 'banana', 'apple'),
 'veggie' => array('carrot', 'collard', 'pea'));
// recursive count
echo count($food, COUNT_RECURSIVE); // output 8
// normal count
echo count($food); // output 2
?>

Source

• Peter Mortensen: What is a "recursive array"? With some kind of tree structure? Or something else?
• Peter Mortensen: This doesn't answer the question. The gist of the question is the overwriting of items during the definition, not how the length of associative arrays is defined/computed in general.

Answer 3

The array you have created only has two elements in it, hence count returning 2. You are overwriting elements; to see what’s in your array, use:

print_r($a);