$_GET for URL parameters in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the $_GET superglobal in PHP?

The $_GET superglobal is used to collect data sent in the URL parameters (query string) of an HTTP GET request.

beginner

How do you access a URL parameter named name using $_GET?

You access it by using $_GET['name']. For example, if the URL is example.com?name=John, then $_GET['name'] will be John.

beginner

What will $_GET contain if the URL is example.com?page=3&sort=asc?

$_GET will be an associative array with keys and values: ['page' => '3', 'sort' => 'asc'].

intermediate

Why should you validate or sanitize data from $_GET before using it?

Because URL parameters come from the user and can be manipulated, they may contain harmful or unexpected data. Validating or sanitizing helps prevent security issues like XSS or SQL injection.

beginner

How can you check if a URL parameter exists before using it?

You can use isset($_GET['param_name']) to check if the parameter exists to avoid errors when accessing it.

What does $_GET['id'] represent in PHP?

A A cookie named 'id'

B The value of the URL parameter named 'id'

C A session variable named 'id'

D A POST form field named 'id'

$_GET['id'] holds the value of the URL parameter 'id' sent via HTTP GET.

If the URL is example.com?color=blue, what will isset($_GET['color']) return?

A error

B false

C null

D true

The parameter 'color' exists in the URL, so isset($_GET['color']) returns true.

Which HTTP method sends data visible in the URL?

A GET

B POST

C PUT

D DELETE

GET requests send data as URL parameters, visible in the address bar.

Why should you never trust data from $_GET directly?

A It is only accessible by the server

B It is always encrypted

C It can be manipulated by users

D It is always empty

Users can change URL parameters, so data from $_GET can be unsafe without validation.

What type of data structure is $_GET in PHP?

A Associative array

B Indexed array

C Object

D String

$_GET is an associative array where keys are parameter names and values are parameter values.

Explain how to retrieve and safely use a URL parameter in PHP using $_GET.

Think about checking existence and cleaning the data before use.

Describe what happens when a user visits a URL with parameters and how PHP makes those parameters available.

Focus on the flow from URL to PHP variable.