Autor: Codenga 29.09.2023

PHP - Sample Interview Questions

Test your knowledge of the PHP language. We have prepared 10 sample questions that often come up in recruitment interviews. They cover a wide range of PHP basics concepts.

10 PHP Questions - Test Your Skills

Question 1

How do you add a new element to the end of an array in PHP?

A) array_unshift()
B) array_push()
C) array_shift()
D) array_pop()

Correct answer: B. You can use the built-in function array_push() to add an element to the end of an array.

Question 2

What will be the result of executing the following function in PHP?

function addNumbers($num1, $num2 = 10) {
    return $num1 + $num2;
}
echo addNumbers(5);

A) 5
B) 10
C) 15
D) Error

Correct answer: C. This is an example of a function with a default value for the $num2 parameter (which is 10). We provided a value only for the first parameter, so the second one will have the default value.

Question 3

What will be displayed on the page after executing the following script?

function multiplyByTwo(&$num) {
    $num *= 2;
}

$a = 4;
multiplyByTwo($a);
echo $a;

A) 2
B) 4
C) 8
D) 16

Correct answer: C. This involves passing values by reference, which means the original value of variable $a will be changed.

Question 4

How do you define a constant in PHP?

A) const PI = 3.1415;
B) define(PI, 3.1415);
C) define("PI", 3.1415);
D) PI = 3.1415;

Correct answers: A, C. There are two ways to define constants in PHP.

Question 5

What value will be assigned to the $result variable?

$num1 = 10;
$num2 = 5;
$result = ($num1 > $num2) ? ">" : "<=";
echo $result;

A) >
B) <=
C) ?

Correct answer: A. This code includes a ternary operator, which is a simple way to write conditional statements.

Question 6

What type of error will you get if the file you are trying to include does not exist?

require 'file_not_exists.php';

A) Notice
B) Warning
C) Fatal error
D) Parse error

Correct answer: C. Attempting to include a non-existent file using the require statement will result in a Fatal Error.

Question 7

Which of the following mathematical functions rounds a number up?

A) floor()
B) round()
C) ceil()
D) rand()

Correct answer: C. To round a number up, you can use the ceil() function.

Question 8

How can you assign a value to a session variable in PHP?

A) create_session_variable('username', 'John');
B) $_SESSION['username'] = 'John';
C) assign_session_value('username', 'John');
D) set_session_variable('username', 'John');

Correct answer: B. This is an example of a session variable ($_SESSION).

Question 9

Which of the following statements about interfaces in PHP is true?

A) Interfaces can contain method implementations.
B) A class can implement multiple interfaces.
C) Interfaces can inherit from other interfaces.
D) Interfaces can have their own fields.

Correct answers: B, C.

Question 10

How do you send an email using PHP?

$to = "example@example.com";
$subject = "subject";
$message = "message";
$headers = "From: sender@example.com";

A) send_email($to, $subject, $message, $headers);
B) Email::send($to, $subject, $message, $headers);
C) PHPMailer::send($to, $subject, $message, $headers);
D) mail($to, $subject, $message, $headers);

Correct answer: D. To send an email, you can use the mail() function and pass all the necessary parameters.