What are arrays in PHP, and how do I create them?
Jun 27, 2025 am 12:25 AM
An array in PHP is a container that stores multiple values, accessible via indexes or custom keys. 1. To create a basic array, you can use the array() function or phrase syntax []; 2. The index array automatically allocates numeric keys starting from 0; 3. Associative arrays allow custom keys such as "name" and "age"; 4. Multi-dimensional arrays can nest arrays in the array to achieve structured data storage; 5. Multiple types can be mixed in the array, and the content can be viewed by print_r or var_dump.
Arrays in PHP are like containers that let you store multiple values ??in a single variable. Instead of having separate variables for each item, you can group them together and access them by their position (called an index) or a custom key.
How to Create a Basic Array
The simplest way to create an array is using the array() function or the shorter [] syntax introduced in PHP 5.4.
Here's how:
$fruits = array("apple", "banana", "orange");
// Or using short syntax:
$fruits = ["apple", "banana", "orange"]; Each value gets an automatic numeric index starting from 0. So "apple" is at index 0, "banana" at 1, and so on.
You can access any value like this:
echo $fruits[1]; // Outputs: banana
This kind of array is called an indexed array .
Associative Arrays: Use Custom Keys
If you want to assign your own keys instead of relying on numeric indexes, you're working with an associated array .
$person = array("name" => "John", "age" => 30);
// Short syntax:
$person = ["name" => "John", "age" => 30];Now you can access values ??using meaningful keys:
echo $person["name"]; // Outputs: John
This is especially useful when dealing with data like user info, settings, or form inputs where labels matter.
Multidimensional Arrays: Store Arrays Inside Arrays
Sometimes, you need more structure — like rows and columns. That's where multidimensional arrays come in handy.
For example:
$users = [
["name" => "Alice", "age" => 25],
["name" => "Bob", "age" => 30]
];To get Alice's age:
echo $users[0]["age"]; // Outputs: 25
These are common when working with database results or tabular data.
A Few Things to Keep in Mind
- You can mix types inside an array — strings, numbers, even other arrays.
- PHP arrays are zero-indexed by default unless you specify keys manually.
- Use
print_r($array)orvar_dump($array)to see what's inside an array during testing.
Basically that's it.
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