PHP How to Convert Object to Array Easily

In PHP, you can convert an object to an array by using (array)$object to cast it or get_object_vars($object) to get its properties as an array.

Examples

Inputobject with properties {"name":"John", "age":30}

Output{"name":"John", "age":30}

Inputempty object {}

Output{}

Inputobject with nested object {"person":{"name":"Anna"}}

Output{"person":{"name":"Anna"}}

How to Think About It

To convert an object to an array in PHP, think about extracting the object's properties and their values into a list format. You can do this by casting the object to an array or by using a built-in function that returns the object's properties as an array. This helps when you want to work with array functions or need a simpler data structure.

Algorithm

1

Get the object you want to convert.

2

Use a method to extract its properties as an array.

3

Return or use the resulting array.

Code

php

<?php
$obj = new stdClass();
$obj->name = "John";
$obj->age = 30;

// Method 1: Casting
$array1 = (array)$obj;
print_r($array1);

// Method 2: get_object_vars
$array2 = get_object_vars($obj);
print_r($array2);
?>

Output

Array
(
    [name] => John
    [age] => 30
)
Array
(
    [name] => John
    [age] => 30
)

Dry Run

Let's trace converting an object with properties name='John' and age=30 to an array.

1

Create object

Object has properties: name='John', age=30

2

Cast object to array

Resulting array: ['name' => 'John', 'age' => 30]

3

Use get_object_vars

Returns array: ['name' => 'John', 'age' => 30]

Step	Action	Result
1	Create object	{name: 'John', age: 30}
2	Cast to array	['name' => 'John', 'age' => 30]
3	get_object_vars	['name' => 'John', 'age' => 30]

Why This Works

Step 1: Casting object to array

Using (array)$object converts the object properties into an associative array with keys as property names.

Step 2: Using get_object_vars function

The get_object_vars() function returns an associative array of accessible properties of the object.

Alternative Approaches

json encode and decode

php

<?php
$obj = new stdClass();
$obj->name = "John";
$obj->age = 30;

$array = json_decode(json_encode($obj), true);
print_r($array);
?>

This method converts the object to JSON string and back to array, useful for nested objects but slower.

Complexity: O(n) time, O(n) space

Time Complexity

Converting an object to an array requires visiting each property once, so it takes linear time relative to the number of properties.

Space Complexity

A new array is created to hold the properties, so space usage grows linearly with the number of properties.

Which Approach is Fastest?

Casting with (array) is fastest and simplest; get_object_vars() is similar; JSON encode/decode is slower but handles nested objects better.

Approach	Time	Space	Best For
(array) cast	O(n)	O(n)	Simple, shallow objects
get_object_vars()	O(n)	O(n)	Accessible properties only
json encode/decode	O(n)	O(n)	Nested objects, deep conversion