php.array_chunk()

An array in PHP is a data structure that stores a collection of values, such as numbers or strings, in a linear order. It can be created by using the array() constructor or by using square brackets [] with comma-separated values inside.

In this tutorial, we will learn how we can split an array into chunks using the array_chunk() method provided in the PHP standard library.

Function Syntax

The following demonstrates the function definition:

array_chunk(array $array, int $length, bool $preserve_keys = false): array

Function Parameters

The function accepts three main parameters:

1. array - represents the input array on which the function is applied.
2. length- this parameter defines the size of each chunk.
3. preserve_keys - this is a boolean value that determines whether the keys of the array are preserved or not. If set to False, the function will re-index the chunks in a numerical pattern.

Function Return Value

The function will return a multidimensional, numerically indexed array starting with 0 for each dimension.

NOTE: The function will return a ValueError if the value of the length parameter is less than 1.

Example

The following example demonstrates how to use the array_chunk() method to divide the array into various chunks.

// define an input array
$inputArray = array('apple', 'banana', 'cherry', 'date', 'elderberry', 'fig', 'grape');

// divide the input array into three chunks
$chunks = array_chunk($inputArray, 3);

// output the chunks
print_r($chunks);

In this case, we define an input array containing 7 elements. We then use the array_chunk() function to divide the array into three chunks with each chunk containing three elements. The last chunk will contain less than 3 elements as the input array is not divisible equally by the chunk size.

Resulting output:

Array
(
    [0] => Array
        (
            [0] => apple
            [1] => banana
            [2] => cherry
        )

    [1] => Array
        (
            [0] => date
            [1] => elderberry
            [2] => fig
        )

    [2] => Array
        (
            [0] => grape
        )

)

And there you have it.

Conclusion

In this tutorial, we explored how we can use the array_chunk() function in PHP in order to split an input array into various number of chunks.