How to Count Array Elements in PHP Using count(), array_count_values() and array_filter()

In PHP, arrays are a fundamental data type, and counting elements or occurrences can be done with built-in functions. This guide shows how to count the total number of elements, the number of distinct elements, and the occurrences of a specific element.

1. Counting the total number of array elements

The count() function returns the number of elements in an array.

$fruits = array("apple", "orange", "banana", "pear");
echo count($fruits); // outputs 4

The code defines an array $fruits with four items and uses count() to output the value 4.

2. Counting distinct elements in an array

The array_count_values() function returns an associative array where each key is a distinct value from the original array and each value is the number of times that key appears.

$fruits = array("apple", "orange", "banana", "pear", "apple", "apple");
$count_fruits = array_count_values($fruits);
print_r($count_fruits);

The result is:

Array (
    [apple] => 3
    [orange] => 1
    [banana] => 1
    [pear] => 1
)

This shows that "apple" appears three times, while "orange", "banana", and "pear" each appear once.

3. Counting the occurrences of a specific element

You can use array_count_values() together with array indexing, a foreach loop, or array_filter() with an anonymous function.

Using a foreach loop:

$fruits = array("apple", "orange", "banana", "pear", "apple", "apple");
$count_apple = 0;
foreach ($fruits as $fruit) {
    if ($fruit == "apple") {
        $count_apple++;
    }
}
echo $count_apple; // outputs 3

Using array_filter() with an anonymous function:

$fruits = array("apple", "orange", "banana", "pear", "apple", "apple");
$count_apple = count(array_filter($fruits, function($fruit) {
    return $fruit == "apple";
}));
echo $count_apple; // outputs 3

Both approaches count how many times "apple" appears in the original $fruits array, resulting in the value 3.

In summary, PHP provides several ways— count(), array_count_values(), foreach loops, and array_filter() with anonymous functions—to count array elements, and the choice depends on the specific scenario and performance considerations.