PHP Arrays

What is an Array?

An array is a data structure in PHP that can hold multiple values in a single variable. Arrays allow you to store collections of related data, such as a list of names or numbers.

Types of Arrays

PHP supports three types of arrays:

• Indexed Arrays: Arrays with a numeric index (0, 1, 2, etc.).
• Associative Arrays: Arrays that use named keys to access values.
• Multidimensional Arrays: Arrays that contain one or more arrays.

Creating Arrays

Indexed Arrays

<?php
$fruits = array("Apple", "Banana", "Cherry");
?>

Here, the array $fruits contains three indexed values.

Associative Arrays

<?php
$person = array(
    "name" => "John Doe",
    "age" => 30,
    "city" => "New York"
);
?>

This array uses named keys (like name, age, city) to access values.

Multidimensional Arrays

<?php
$students = array(
    array("John", 25),
    array("Alice", 22),
    array("Bob", 23)
);
?>

This array contains multiple arrays, allowing you to store complex data structures.

Accessing Array Elements

Access elements in an array using their index or key:

Indexed Arrays

<?php
echo $fruits[1]; // Outputs: Banana
?>

Associative Arrays

<?php
echo $person["name"]; // Outputs: John Doe
?>

Array Functions

PHP provides many built-in functions to manipulate arrays:

• count(): Returns the number of elements in an array.
• array_push(): Adds one or more elements to the end of an array.
• array_pop(): Removes the last element from an array.
• array_merge(): Merges two or more arrays into one.
• in_array(): Checks if a value exists in an array.

Example of Array Functions

<?php
$numbers = array(1, 2, 3);

// Count elements
echo count($numbers); // Outputs: 3

// Add an element
array_push($numbers, 4); // $numbers is now [1, 2, 3, 4]

// Remove the last element
array_pop($numbers); // $numbers is now [1, 2, 3]
?>

Looping Through Arrays

You can loop through arrays using foreach:

<?php
foreach ($fruits as $fruit) {
    echo $fruit . "<br>"; // Outputs each fruit
}
?>

Conclusion

Arrays are a powerful feature in PHP that allow you to store and manipulate collections of data. Understanding how to create, access, and manage arrays is essential for effective programming in PHP.