1. What does PHP stand for?
- a) PHP: Hypertext Preprocessor
- b) Private Home Page
- c) Personal Hypertext Processor
- d) Preprocessed Hypertext Page
Answer: A - PHP originally stood for "Personal Home Page" but now stands for "PHP: Hypertext Preprocessor" (a recursive acronym).
2. Which of the following is the correct way to start a PHP block?
- a) <?php
- b) <?>
- c) <script language="php">
- d) All of the above
Answer: D - PHP code can be started with <?php (recommended), <? (short tags), or <script language="php">.
3. What is the result of echo "1" + "2";?
- a) 3
- b) 12
- c) "12"
- d) Error
Answer: A - PHP performs type juggling and converts the strings to numbers when using the + operator.
4. Which superglobal holds information about headers, paths, and script locations?
- a) $_SERVER
- b) $_GET
- c) $_SESSION
- d) $_ENV
Answer: A - $_SERVER contains server and execution environment information.
5. What is the correct way to create a constant in PHP?
- a) define("CONSTANT", "value");
- b) const CONSTANT = "value";
- c) $constant = "value";
- d) Both A and B
Answer: D - Constants can be defined with define() or the const keyword (in class definitions or at compile time).
6. Which function converts a string to lowercase?
- a) strtolower()
- b) strtoupper()
- c) ucfirst()
- d) lcfirst()
Answer: A - strtolower() converts a string to lowercase.
7. What does the === operator check?
- a) Value and type equality
- b) Only value equality
- c) Only type equality
- d) Reference equality
Answer: A - === checks both value and type (strict comparison).
8. Which function returns the length of a string?
- a) strlen()
- b) count()
- c) sizeof()
- d) length()
Answer: A - strlen() returns the length of a string in bytes.
9. What is the default session storage mechanism in PHP?
- a) Files on the server
- b) Browser cookies
- c) Database
- d) Memory
Answer: A - By default, PHP stores session data in files on the server.
10. Which function is used to redirect to another page?
- a) header()
- b) redirect()
- c) location()
- d) forward()
Answer: A - header("Location: url") is used for page redirection (must be called before any output).
11. What does PDO stand for?
- a) PHP Data Objects
- b) Portable Data Objects
- c) Persistent Database Objects
- d) Predefined Data Objects
Answer: A - PDO stands for PHP Data Objects, a database access layer.
12. Which function is used to check if a variable is an array?
- a) is_array()
- b) is_array()
- c) isArray()
- d) typeOf()
Answer: A - is_array() checks if a variable is an array.
13. What is the correct way to include a file in PHP?
- a) include 'file.php';
- b) require 'file.php';
- c) include_once 'file.php';
- d) All of the above
Answer: D - All are valid, with different behaviors on failure (include continues, require stops) and multiple inclusions.
14. Which function is used to destroy a session?
- a) session_destroy()
- b) session_end()
- c) session_abort()
- d) session_close()
Answer: A - session_destroy() removes all session data.
15. What is the correct way to create a cookie in PHP?
- a) setcookie(name, value, expire);
- b) create_cookie(name, value);
- c) cookie(name, value, expire);
- d) make_cookie(name, value);
Answer: A - setcookie() is used to create cookies in PHP.
16. Which function escapes special characters in a string for SQL queries?
- a) mysqli_real_escape_string()
- b) escape_string()
- c) sql_escape()
- d) mysql_escape()
Answer: A - mysqli_real_escape_string() escapes special characters for SQL (though prepared statements are preferred).
17. What is the correct way to create an array in PHP?
- a) $arr = array(1, 2, 3);
- b) $arr = [1, 2, 3];
- c) $arr = new Array(1, 2, 3);
- d) Both A and B
Answer: D - Both array() and [] (since PHP 5.4) are valid array syntax.
18. Which function returns the current date and time?
- a) date()
- b) time()
- c) now()
- d) getdate()
Answer: A - date() formats the current timestamp (default) or a specified timestamp.
19. What does the __construct() method do?
- a) It's a class constructor
- b) It destroys an object
- c) It converts an object to a string
- d) It creates a clone of an object
Answer: A - __construct() is called when an object is instantiated.
20. Which function is used to send email in PHP?
- a) mail()
- b) sendmail()
- c) email()
- d) smtp()
Answer: A - The mail() function is used to send email (though libraries like PHPMailer are often preferred).