How can PHP implement inputting numbers?

In PHP, you can use $_POST or $_GET to retrieve user input numbers.

The sample code is presented below:

Retrieve the user inputted number using the $_POST method.

<form method="post" action="">
    <input type="text" name="number">
    <input type="submit" value="Submit">
</form>

<?php
if(isset($_POST['number'])){
    $number = $_POST['number'];
    echo "You entered: " . $number;
}
?>

Retrieve user inputted numbers using the $_GET method.

<form method="get" action="">
    <input type="text" name="number">
    <input type="submit" value="Submit">
</form>

<?php
if(isset($_GET['number'])){
    $number = $_GET['number'];
    echo "You entered: " . $number;
}
?>

Users input numbers into the form input field, and when they submit the form, the PHP code will retrieve the input and display it.