Passing arguments to functions and returning values

Passing Arguments to Functions and Returning Values in PHP:

In PHP, functions can accept arguments (also known as parameters) when they are called. These arguments allow you to pass data to the function, which the function can then use to perform its task. Additionally, functions in PHP can return values back to the code that called them. This mechanism enables functions to process data and provide results for further use in the program. Let's explore how to pass arguments to functions and return values in PHP with examples.

Passing Arguments to Functions:

To pass arguments to a PHP function, you specify them within the parentheses when defining the function. When calling the function, you provide the values for these arguments.

<?php
function greet($name) {
echo "Hello, $name!";
}
greet("John"); // Output: Hello, John!
?>

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In this example, the greet() function accepts a single argument $name, which is used to personalize the greeting message. When the function is called with the argument "John", it outputs "Hello, John!".

Default Argument Values:

PHP allows you to specify default values for function arguments. If a value is not provided for an argument when the function is called, the default value is used instead.

<?php
function greet($name = "Guest") {
echo "Hello, $name!";
}
greet(); // Output: Hello, Guest!
greet("Alice"); // Output: Hello, Alice!
?>

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In this example, if no argument is provided, the function greet() defaults to greeting a guest. However, if an argument such as "Alice" is provided, it uses that value instead.

Returning Values from Functions:

Functions in PHP can return values using the return statement. This allows the function to compute a result and provide it back to the calling code.

<?php
function add($a, $b) {
return $a + $b;
}
$result = add(5, 3);
echo $result; // Output: 8
?>

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In this example, the add() function accepts two arguments $a and $b, adds them together, and returns the result. The returned value is then assigned to the variable $result and echoed to the output.

Multiple Return Values:

Although a PHP function can only return a single value, you can return multiple values by using an array or an object.

<?php
function calculate($a, $b) {
$sum = $a + $b;
$difference = $a - $b;
return [$sum, $difference];
}
list($sum, $difference) = calculate(8, 3);
echo "Sum: $sum, Difference: $difference"; // Output: Sum: 11, Difference: 5
?>

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In this example, the calculate() function returns an array containing the sum and difference of the two arguments $a and $b. The returned array is then unpacked using the list() construct, and its values are assigned to variables $sum and $difference, respectively.

Practical Example:

Let's create a function that calculates the factorial of a number and returns the result.

<?php
function factorial($n) {
$result = 1;
for ($i = 1; $i <= $n; $i++) {
$result *= $i;
}
return $result;
}
echo factorial(5); // Output: 120 (5! = 5 * 4 * 3 * 2 * 1)
?>

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