PHP counts the number of cells or object attributes in an array

php editor Strawberry introduces you how to calculate the number of units or object attributes in a PHP array. In PHP, you can use the count() function to get the number of units in an array, or you can use the count() or sizeof() function to get the number of attributes of an object. These functions can help you quickly and accurately count the number of elements in an array or object, making programming more efficient and easier. Next, let’s learn in detail how to implement these functions in PHP.

Calculate the number of cells or object attributes in the array

Array

• count($array): Count the number of cells in the array, including cells in nested arrays.

<?php
$array = array(1, 2, 3, array(4, 5, 6));
echo count($array); // Output: 4
?>

• sizeof($array): Equivalent to count().

<?php
$array = array(1, 2, 3, array(4, 5, 6));
echo sizeof($array); // Output: 4
?>

Object

The number of object attributes can be calculated by the following method:

• count($object): Count the number of all public attributes of the object.

<?php
class Person {
public $name;
public $age;
}

$person = new Person();
$person->name = "John Doe";
$person->age = 30;
echo count($person); // Output: 2
?>

• get_object_vars($object): Returns an associative array containing all public attributes of the object. The key of the array is the attribute name and the value is the attribute value.

<?php
class Person {
public $name;
public $age;
}

$person = new Person();
$person->name = "John Doe";
$person->age = 30;
$properties = get_object_vars($person);
echo count($properties); // Output: 2
?>

• array_keys($object): Returns an array containing all public property names of the object.

<?php
class Person {
public $name;
public $age;
}

$person = new Person();
$person->name = "John Doe";
$person->age = 30;
$propertyNames = array_keys(get_object_vars($person));
echo count($propertyNames); // Output: 2
?>

Nested Arrays and Objects

If an array or object contains other arrays or objects, you can use the recursive method to calculate the total number of its cells or properties.

<?php
function countNestedArray($array) {
$count = 0;
foreach ($array as $value) {
if (is_array($value)) {
$count = countNestedArray($value);
} else {
$count ;
}
}
return $count;
}
?>

<?php
class Person {
public $name;
public $age;
public $children;
}

function countNestedObject($object) {
$count = 0;
foreach ($object as $property => $value) {
if (is_object($value)) {
$count = countNestedObject($value);
} else {
$count ;
}
}
return $count;
}
?>

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