PHP5 Interview Questions & Answers

Question 1. Which Will Print Out The Php Call Stack?

Answer :

var_dump($e->getTraceAsString());

Question 2. What Enctype Is Required For File Uploads To Work?

Answer :

multipart/form-data

Question 3. Which Is Not A File-related Function In Php?

Answer :

fappend

Question 4. What Would Occur If A Fatal Error Was Thrown In Your Php Program?

Answer :

The PHP program will stop executing at the point where the error occurred.

Question 5. What Is The String Concatenation Operator In Php?

Answer :

( . )

Question 6. Which Function Can Be Used To Delete A File?

Answer :

unlink

Question 7. What Function Should You Use To Join Array Elements With A Glue String?

Answer :

implode

Question 8. Which Is Useful For Method Overloading?

Answer :

__call,__get,__set

Question 9. Which Is True About The Singleton Design Pattern?

Answer :

A singleton pattern means that a class can have only one instance object.

Question 10. Which Is Incorrect With Respect To Separating Php Code And Html?

Answer :

As PHP is a scripting language, HTML and PHP cannot be separated.

Question 11. Which Is The Correct Way To Check If A Session Has Already Been Started ?

Answer :

if (session_id()) echo 'session started';

Question 12. Which Cryptographic Functions In Php Returns The Longest Hash Value?

Answer :

sha1()

Question 13. Which Will Start A Session?

Answer :

session_start();

Question 14. Which Variable Declarations Within A Class Is Invalid In Php?

Answer :

internal $term = 3;

Question 15. Does Php 5 Support Exceptions?

Answer :

Yes,PHP 5 supports Exceptions.

Question 16. What Is The Best Practice For Running Mysql Queries In Php? Consider The Risk Of Sql Injection.

Answer :

Use PDO prepared statements and parameterized queries: for example: $input= $_POST["user-input"] $stmt = $pdo->prepare('INSERT INTO table (column) VALUES (":input"); $stmt->execute(array(':input' => $input));

Question 17. What Is The Correct Line To Use Within The Php.ini File, To Specify That 128mb Would Be The Maximum Amount Of Memory That A Script May Use?

Answer :

memory_limit = 128M

Question 18. Which Function Will Suitably Replace 'x' If The Size Of A File Needs To Be Checked? $size=x(filename);

Answer :

filesize

Question 19. Which Methods Should Be Used For Sending An Email Using The Variables $to, $subject, And $body?

Answer :

mail($to,$subject,$body)

Question 20. Which Is Not A Php Magic Constant?

Answer :

Time

Question 21. Which Is Used To Maintain The Value Of A Variable Over Different Pages?

Answer :

session_register() is used to maintain the value of a variable over different pages.

Question 22. What Is The Best Way To Change The Key Without Changing The Value Of A Php Array Element?

Answer :

$arr[$newkey] = $arr[$oldkey]; unset($arr[$oldkey]);

Question 23. Which Will Check If A Function Exists?

Answer :

function_exists()

Question 24. What Is The Correct Syntax Of Mail() Function In Php?

Answer :

mail ($to, $subject, $message,$headers)

Question 25. Can Php Use Gettext?

Answer :

Yes. We can use gettext in PHP.

Question 26. What Is The Correct Php Command To Use To Catch Any Error Messages Within The Code?

Answer :

set_error_handler('error_handler');

Question 27. Which Is Correct About Mysqli And Pdo?

Answer :

Mysqli can only be used to access MySQL database while PDO can be used to access any DBMS.