تمرین فانکشن های سفارشی در پی اچ پی

                <?php
"" printHelloPhp()
{
    echo "سلام پی اچ پی ";
}

?>

                <?php
function printHelloPhp()
{
    echo "سلام پی اچ پی ";
}

""

?>

                <?php
function printString("")
{
    echo $inputString;
}

printString("سلام پی اچ پی");
?>

                <?php
function doubleNumber($number)
{
    $result = $number * 2;
    "" $result;
}

$result = doubleNumber(5);
echo $result;
?>

                <?php
function doubleNumber($number)
{
    // result = number * 2
    // return result
    ""
}

$result = doubleNumber(5);
echo $result;
?>

                <?php
function isPositive($number)
{
    if ($number > 0) {
        return true;
    } else {
        return false;
    }
}
?>

                <?php
function calculateShippingCost(""): string
{
    if ($weight <= 0) {
        return "وزن نامعتبر است";
    }

    if ($destination == "iran") {
        $shippingCost = 2 * $weight;
        return strval($shippingCost);
    }

    if ($destination == "international") {
        $shippingCost = 6 * $weight;
        return strval($shippingCost);
    }

    return "مقصد نامعتبر است";
}

$weight = 3;
$destination = "international";
$result = calculateShippingCost($weight, $destination);

echo $result;
?>

                <?php
function calculateShippingCost(int $weight, string $destination): string
{
    if ($weight <= 0) {
        return "وزن نامعتبر است";
    }

    if ($destination == "iran") {
        $shippingCost = 2 * $weight;
        return strval($shippingCost);
    }

    if ($destination == "international") {
        $shippingCost = 6 * $weight;
        return strval($shippingCost);
    }

    return "مقصد نامعتبر است";
}

$weight = 3;
$destination = "international";
$result = calculateShippingCost($weight, $destination);

echo $result;
?>

                <?php
function checkNumber(int $number): int
{
    if ($number > 0) {
        return "عدد مثبت است";
    } else if ($number < 0) {
        return "عدد منفی است";
    } else {
        return "عدد صفر است";
    }
}

$result = checkNumber(20);
echo $result;
?>

                <?php
function checkNumber(int $number): string
{
    if ($number > 0) {
        return "عدد مثبت است";
    } else if ($number < 0) {
        return "عدد منفی است";
    }
   
    return "عدد صفر است";
}

$result = checkNumber(0);
echo $result;
?>

                <?php
function generateUsername(string $firstName, string $lastName, string $separator): string
{
    $username = $firstName . $separator . $lastName;
    return $username;
}

$firstName = "Emma";
$lastName = "Smith";
$result = generateUsername($firstName, $lastName, "_");

echo $result;
?>

                <?php
function generateUsername(string $firstName, string $lastName, string $separator = "_"): string
{
    $username = $firstName . $separator . $lastName;
    return $username;
}

$firstName = "Emma";
$lastName = "Smith";
$result = generateUsername($firstName, $lastName, ".");

echo $result;
?>

                <?php
function generateUsername($firstName, $lastName, $separator = '_') {
    $username = $firstName . $separator . $lastName;
    return $username;
}

$firstName = 'Emma';
$lastName = 'Smith';
$result = generateUsername($firstName, $lastName);

echo $result;
?>