PHP
Project final - Contact form
Combine all parts and finalize a working contact form.
Combining all pieces
In the final lesson you combine all parts with a processSubmission() function. It does the following in order: starts the session with session_start(), reads data from $_POST, escapes it with htmlspecialchars and fills a ContactMessage instance.
Then it runs validateMessage($m); if there are errors it returns "skip". When there are no errors it processes the file with handleUpload($_FILES['screenshot']) and stores the message in the session with $_SESSION['messages'][] = $m. Finally it returns "ok".
Storing messages in a session
The session_start() call opens the session; afterwards you can write to the $_SESSION superglobal. To store messages you write $_SESSION['messages'][] = $m; this appends each submission to the end of the list.
On later requests $_SESSION['messages'] is loaded automatically, so you can see all submitted messages in one place. The session ends when the user clears the cookie or it expires.
Exercise Write the processSubmission function
Write a processSubmission(): string function. Inside, call session_start();. Create $m = new ContactMessage();; write $m->name = htmlspecialchars($_POST['name'] ?? ''); and the same pattern for email and message. Validate with $errors = validateMessage($m);; if count($errors) > 0 return "skip". Call handleUpload($_FILES['screenshot'] ?? []);. Append to the session with $_SESSION['messages'][] = $m; and return "ok". For testing, set $_POST and $_FILES by hand; write echo processSubmission();.
Show example solution
string { session_start(); $m = new ContactMessage(); $m->name = htmlspecialchars($_POST['name'] ?? ''); $m->email = htmlspecialchars($_POST['email'] ?? ''); $m->message = htmlspecialchars($_POST['message'] ?? ''); $errors = validateMessage($m); if (count($errors) > 0) { return "skip"; } handleUpload($_FILES['screenshot'] ?? []); $_SESSION['messages'][] = $m; return "ok"; }. Set $_POST and $_FILES by hand; echo processSubmission();.
Example solution:
<?php
// Combine all pieces
class ContactMessage {
public string $name = "";
public string $email = "";
public string $message = "";
}
function renderForm(): string {
return '<form method="post" action="/contact.php">'
. '<label>Name: <input type="text" name="name"></label>'
. '<label>Email: <input type="email" name="email"></label>'
. '<label>Message: <textarea name="message"></textarea></label>'
. '<input type="submit" value="Send">'
. '</form>';
}
function validateMessage(ContactMessage $m): array {
$errors = [];
if (empty($m->name)) {
$errors[] = "Name empty";
}
if (empty($m->email) || filter_var($m->email, FILTER_VALIDATE_EMAIL) === false) {
$errors[] = "Email invalid";
}
return $errors;
}
function handleUpload(array $file): string {
if ($file['error'] !== UPLOAD_ERR_OK) {
return "skip";
}
if ($file['size'] > 2 * 1024 * 1024) {
return "skip";
}
$dest = __DIR__ . "/uploads/" . basename($file['name']);
move_uploaded_file($file['tmp_name'], $dest);
return "ok";
}
function processSubmission(): string {
session_start();
$m = new ContactMessage();
$m->name = htmlspecialchars($_POST['name'] ?? '');
$m->email = htmlspecialchars($_POST['email'] ?? '');
$m->message = htmlspecialchars($_POST['message'] ?? '');
$errors = validateMessage($m);
if (count($errors) > 0) {
return "skip";
}
handleUpload($_FILES['screenshot'] ?? []);
$_SESSION['messages'][] = $m;
return "ok";
}
$_POST = ['name' => 'Alex', 'email' => 'alex@example.com', 'message' => 'Hello'];
$_FILES = ['screenshot' => ['name' => 'image.png', 'type' => 'image/png', 'tmp_name' => '/tmp/temp.tmp', 'error' => UPLOAD_ERR_OK, 'size' => 1024]];
echo processSubmission();
Test yourself
-
Where do you store contact form messages between requests?
- $_GET
- $_POST
- $_SESSION
- $_FILES
Show answer
$_SESSION — Correct. $_SESSION keeps data on the server for the whole session; it survives across requests.
-
Match the project final concepts
- session_start()
- Session start
- $_SESSION['messages']
- Message list
- validateMessage()
- Validation
- handleUpload()
- File move
-
Complete the session_start call
____;
$_SESSION['messages'][] = $m;
Show answer
session_start();
$_SESSION['messages'][] = $m;
Next lesson: The try/catch block
