Accessing user input is one of the most essential tasks in PHP development—whether it’s capturing form data, URL parameters, cookies, or session values. PHP makes this easy using Superglobal Arrays, which are available in all scopes without requiring special initialization.
How PHP Receives User Input
PHP collects user input through predefined superglobal arrays such as:
1. $_GET – Accessing Data Sent Through URL
Used when data is sent via URL query strings.
Example URL:
example.com/form.php?name=Sagar&age=23
PHP Code:
$name = $_GET['name'];
$age = $_GET['age'];
echo "Name: $name, Age: $age";
2. $_POST – Accessing Data Sent Through HTML Forms
Used when forms are submitted using the POST method.
HTML Form:
<form method="POST" action="submit.php">
<input type="text" name="username">
<button type="submit">Submit</button>
</form>
submit.php:
$username = $_POST['username'];
echo "Username: $username";
POST is more secure than GET because values are not visible in the URL.
3. $_REQUEST – Combines GET, POST, and COOKIE
Useful when you don’t know the method used.
$user = $_REQUEST['user'];
However, using $_REQUEST is less secure and less predictable—use only when necessary.
4. $_FILES – Accessing Uploaded Files
Handles file uploads securely.
$fileName = $_FILES['upload']['name'];
$temp = $_FILES['upload']['tmp_name'];
move_uploaded_file($temp, "uploads/".$fileName);
5. $_COOKIE – Accessing User Cookies
echo $_COOKIE["userToken"];
6. $_SESSION – Accessing Session Data
session_start();
echo $_SESSION["username"];
Validating User Input
Always validate input to avoid security issues like SQL injection and XSS.
Example:
$name = htmlspecialchars($_POST['name']);
$email = filter_var($_POST['email'], FILTER_VALIDATE_EMAIL);
Final Summary
PHP makes accessing user input simple using its built-in superglobal variables. Forms, URLs, cookies, and sessions can all be processed easily and securely when combined with proper validation and sanitization.
Citations
🔗 View other articles about PHP:
http://savanka.com/category/learn/php/
🔗 External PHP Documentation:
https://www.php.net/manual/en/
