PHP Basics Tutorial – Functions in PHP

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Learn about functions in PHP, including how to define them, pass arguments, return values, and use default parameters. This guide includes clear examples for beginners.

What is a Function?

A function is a block of reusable code that performs a specific task.

Defining a Function

<?php
function sayHello() {
    echo "Hello, PHP!";
}

sayHello();  // Output: Hello, PHP!
?>

Functions with Arguments

Functions can accept parameters to make them more flexible.

<?php
function greet($name) {
    echo "Hello, $name!";
}

greet("Alice");  // Output: Hello, Alice!
?>

Returning Values

Functions can return values using the return statement.

<?php
function add($a, $b) {
    return $a + $b;
}

echo add(5, 3);  // Output: 8
?>

Default Argument Values

You can provide default values for function arguments.

<?php
function setHeight($height = 150) {
    echo "The height is: $height cm";
}

setHeight();  // Output: The height is: 150 cm
setHeight(180);  // Output: The height is: 180 cm
?>