PHP Superglobal $_REQUEST

1. What is the $_REQUEST Superglobal?

The $_REQUEST superglobal is an associative array that contains data from the $_GET, $_POST, and $_COOKIE superglobals. It allows you to access user input regardless of the method used to send the data.

2. How $_REQUEST Works

When a user submits data from a form, PHP populates the $_REQUEST superglobal with that data. It combines input from various sources, making it easier to handle user submissions.

However, it's important to note that using $_REQUEST can lead to security vulnerabilities, as it can contain data from cookies, which may not be expected. Therefore, it's recommended to use $_GET and $_POST explicitly when possible.

3. Accessing Request Data

To access data from the $_REQUEST superglobal, you can simply use the keys corresponding to the input fields in your HTML form. Here's an example:

<?php
// Assuming a form submission with input field name "username"
$username = $_REQUEST['username'];
echo "Username: " . htmlspecialchars($username);
?>

In this example, the value of the input field named username is accessed from the $_REQUEST superglobal.

4. Example: Using $_REQUEST with a Form

Here’s a complete example that demonstrates how to use $_REQUEST with a simple form:

<form action="" method="POST">
    <label for="username">Username:</label>
    <input type="text" name="username" id="username" required>
    <input type="submit" value="Submit">
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $username = $_REQUEST['username'];
    echo "Hello, " . htmlspecialchars($username) . "!";
}
?>

This form collects a username and displays a greeting upon submission.

5. Handling Multiple Inputs

You can also handle multiple input fields using the $_REQUEST superglobal:

<form action="" method="POST">
    <label for="first_name">First Name:</label>
    <input type="text" name="first_name" id="first_name" required>

    <label for="last_name">Last Name:</label>
    <input type="text" name="last_name" id="last_name" required>

    <input type="submit" value="Submit">
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $firstName = $_REQUEST['first_name'];
    $lastName = $_REQUEST['last_name'];
    echo "Welcome, " . htmlspecialchars($firstName) . " " . htmlspecialchars($lastName) . "!";
}
?>

This example collects both first and last names and displays a welcome message.

6. Conclusion

The $_REQUEST superglobal is a convenient way to access data submitted by users through forms. However, it's essential to validate and sanitize the input to ensure security and data integrity.

For better control over data handling, consider using $_GET and $_POST directly based on the context of your application.