is_array() Function in PHP: Complete Guide with Examples

When working with PHP, it’s important to validate data types to avoid errors. One common requirement is checking whether a variable is an array. This is where the is_array() function becomes very useful.

In this article, we will cover:

• What is is_array() in PHP?
• Syntax of is_array()
• Practical examples
• Real-world use cases
• FAQs about is_array()

What is is_array() in PHP?

The is_array() function in PHP is used to check whether a variable is an array or not.
It returns:

• TRUE if the variable is an array.
• FALSE if it is not.

Why use is_array()?
When handling user input, API data, or database results, it’s important to confirm the data type before processing it. is_array() helps prevent runtime errors by ensuring you're dealing with an array before performing array operations.

Syntax of is_array()

bool is_array(mixed $variable)

• Parameter:
  • $variable – The variable you want to check.
• Return Type:
  • bool – Returns TRUE if the variable is an array, FALSE otherwise.

Examples of is_array() in PHP

Example 1: Basic Usage

<?php
$data = [1, 2, 3];

if (is_array($data)) {
    echo "Yes, it is an array.";
} else {
    echo "No, it is not an array.";
}
?>

Output:

Yes, it is an array.

Example 2: Checking a String

<?php
$data = "Hello, World!";

if (is_array($data)) {
    echo "It is an array.";
} else {
    echo "It is not an array.";
}
?>

Output:

It is not an array.

Example 3: Checking an Empty Array

<?php
$data = [];

if (is_array($data)) {
    echo "It is an array, but empty.";
} else {
    echo "It is not an array.";
}
?>

Output:

It is an array, but empty.

Note:
Even if the array is empty, is_array() still returns TRUE.

Real-World Use Case for is_array()

Imagine you are receiving data from an API. Sometimes the API might return a single object instead of an array of objects. You can safely handle this using is_array():

<?php
$response = getApiResponse(); // Assume this function gets the API data

if (is_array($response)) {
    foreach ($response as $item) {
        echo $item['name'] . "<br>";
    }
} else {
    echo "Unexpected response format.";
}
?>

FAQs About is_array() in PHP

Q1: Is an object considered an array in PHP?
Answer: No. Objects are a different data type. is_array() will return FALSE for objects.

Q2: What happens if you pass NULL to is_array()?
Answer: It will return FALSE because NULL is not an array.

Q3: How is is_array() different from gettype()?
Answer: is_array() is a direct check for arrays and returns a boolean (TRUE or FALSE), while gettype() returns a string representing the type ("array", "string", etc.).