Take Test: Symfony 7 – PHP – PHP Extensions

Question 1: How do you check at runtime whether an extension is loaded?

Use extension_loaded("mbstring").

Call phpinfo() and parse HTML.

Check getenv("PHP_EXTS").

Use defined("EXT_mbstring").

Question 2: Which statement about PDO is TRUE?

PDO is a full ORM that auto-generates entities.

PDO only works with MySQL.

PDO replaces SQL with a new query language.

PDO abstracts DB access; you still need a specific driver such as pdo_mysql.

Question 3: Pick the correct PDO prepared statement usage for selecting a user by id.

$stmt=$pdo->prepare("SELECT * FROM user WHERE id = :id"); $stmt->execute(["id"=>1]);

$pdo->query("SELECT * FROM user WHERE id = ".$_GET["id"]);

$pdo->prepare("SELECT * FROM user WHERE id = :id")->execute([":id"=>1]);

$pdo->exec("SELECT * FROM user WHERE id = 1");

Question 4: Why use mbstring functions with UTF-8 text?

mbstring counts multibyte characters correctly; byte-based functions may not.

mbstring automatically translates all languages to English.

mbstring is only for binary files.

mbstring disables strlen.

Question 5: Which snippet correctly formats a number for fr_FR using intl?

echo number_format(1234.5,2,","," "); // locale-aware by intl

setlocale(LC_ALL,"fr_FR"); echo NumberFormatter::format(1234.5);

$f=new NumberFormatter("fr_FR", NumberFormatter::DECIMAL); echo $f->format(1234.5);

new IntlFormatter("fr_FR"); echo format(1234.5);

Question 6: Select the minimal cURL snippet to GET a URL and capture the body.

$ch=curl_init(); $body=curl_exec($ch);

$ch=curl_init("https://example.com"); curl_setopt($ch,CURLOPT_RETURNTRANSFER,true); $body=curl_exec($ch); curl_close($ch);

curl_setopt(CURLOPT_URL,"https://example.com"); $body=curl_exec();

$body=file_get_contents($ch);

Question 7: How do you make json_decode throw on invalid JSON?

json_decode_throw($s);

json_decode($s, true, 512, JSON_THROW_ON_ERROR);

json_last_error_throw();

json_assert($s);

Question 8: DOM vs SimpleXML — which is TRUE?

SimpleXML supports XSLT while DOM does not.

DOM cannot load XML from strings.

SimpleXML is deprecated for XML parsing.

DOM is more verbose but provides fine-grained XML manipulation.

Question 9: Which statement about GD and Imagick is accurate?

GD is common and lightweight; Imagick offers broader format support via ImageMagick.

Imagick is built into PHP core and cannot be disabled.

GD cannot resize images.

GD only works with SVG.

Question 10: OpenSSL extension use-case in PHP is mainly…

Rendering HTML templates.

Managing PHP sessions automatically.

Providing cryptographic functions like TLS, encryption, and key handling.

Generating images like GD.

Question 11: Which is a correct statement about the Sodium extension?

It replaces password_hash entirely.

It provides modern crypto APIs; for passwords still use password_hash/verify.

It only offers random_int().

It is unrelated to cryptography.

Question 12: Select the correct way to create a ZIP file with the ZipArchive class.

new Zip("a.zip"); add("hello.txt","hi");

zip_create("a.zip"); zip_add("hello.txt");

ZipArchive::zip("a.zip","hello.txt","hi");

$z=new ZipArchive; $z->open("a.zip",ZipArchive::CREATE); $z->addFromString("hello.txt","hi"); $z->close();

Question 13: What is a Phar archive in PHP?

A single-file PHP application package (archive).

A binary dump of php.ini settings.

A replacement for Composer.

A JSON-only container for configs.

Question 14: Which call validates an email address using the filter extension?

preg_match("/.+@.+/", $email)

filter_input(INPUT_GET, "email", FILTER_SANITIZE_STRING)

htmlspecialchars($email)

filter_var($email, FILTER_VALIDATE_EMAIL)

Question 15: How do you compare HMACs safely to avoid timing attacks?

Use hash_equals($a, $b).

Use === for faster comparison.

Use strcmp which is always constant-time.

Trim both strings and compare.

Question 16: Which snippet gets a file’s MIME type using fileinfo?

mime_type("a.png")

$f=finfo_open(FILEINFO_MIME_TYPE); $m=finfo_file($f,"a.png"); finfo_close($f);

pathinfo("a.png")["mime"]

$_FILES["a"]["type"]

Question 17: PCNTL/POSIX extensions are typically used for…

Handling browser cookies.

Process control and UNIX system calls in CLI contexts.

Rendering PDFs in GD.

Managing MySQL connections via PDO.

Question 18: What does the OPcache extension do?

Compresses responses with gzip.

Encrypts source code at rest.

Caches compiled opcodes to speed up PHP execution.

Automatically updates Composer packages.

Question 19: mysqli vs pdo_mysql — which is TRUE?

mysqli targets only MySQL, while PDO with pdo_mysql offers a generic API.

pdo_mysql is slower because it uses SOAP.

mysqli is deprecated in PHP 8.

PDO cannot use prepared statements.

Question 20: Which statement about the JSON extension in modern PHP is correct?

JSON must be installed separately on every system.

JSON only works on CLI, not FPM.

JSON requires mbstring to be present.

JSON is bundled and enabled by default, providing json_encode/json_decode.