PHP Interview Questions and Answers
PHP earlier stood for Personal Home Pages, but now it stands for Hypertext Pre-processor. PHP is a server-side scripting language that is used for building web pages and applications. We have just added more questions in our question bank for PHP interview questions. This language includes many Frameworks and CMS for creating large websites. Even a non-technical person can create web pages or apps using PHP CMS or frameworks. PHP supports various frameworks and CMS that are used to develop applications.
Before getting confused with the plethora of PHP developer interview questions, you need to ensure the basics. This question will help you to understand the core basics of PHP and make you even more confident enough to jump onto the advanced questions.
| Quick Facts About PHP | |
|---|---|
| What is the latest version of PHP? | 8.0.3, released on 4th March 2021 |
| Who is the developer of PHP? | Rasmus Lerdorf |
| What language does PHP use? | C language |
| PHP License | It is a BSD-style license which does not have the "copyleft" and restrictions associated with GPL. |
- It runs on various platforms, including Windows, Mac OS X, Linux, Unix, etc.
- It is compatible with almost all servers, including Apache and IIS.
- It supports many databases like MySQL, MongoDB, etc
- It is free, easy to learn and runs on the server-side.
- PHP can operate various file operations on the server
Note: This is a list of the most frequently asked PHP interview questions. Please have a good read and if you want to download it, it is available in a PDF format so that you can brush up your theoretical skills on this subject.
Top PHP Developer Interview Questions
It is used to extract a part of the string. It allows three parameters or arguments out of which two are mandatory, and one is optional
echo substr("Hello world",6);
It will return first six characters from a given string.
It is used to dump information about one or more variables. It displays structured data such as the type and value of the given variable.
Example:
$var_name1=12; int(12);
It is used to inserts HTML line breaks ( <br /> or <br /> ) in front of each newline (\n) in a string.
1. isset(): It returns TRUE if the variable exists and has a value other than NULL. It means variables assigned a "", 0, "0", or FALSE are set.
2. empty(): It checks to see if a variable is empty. It interpreted as: "" (an empty string).
isset($var) && !empty($var)
will be equals to !empty($var)
1. mysql_fetch_object: It returns the result from the database as objects. In this field can be accessed as $result->name
2. mysql_fetch_array: It returns result as an array. In this field can be accessed as $result->[name]
Constructor and a Destructor both are special functions which are automatically called when an object is created and destroyed.
class Animal
{
public $name = "Hello";
public function __construct($name)
{
echo "Live HERE";
$this->name = $name;
}
public function __destruct()
{
echo "Destroy here";
}
}
$animal = new Animal("Bob");
echo "My Name is : " . $animal->name;
ctype_upper() function in PHP used to check every and each and every personality of a given string is in uppercase or not. If the string in the top case then it returns TRUE otherwise returns False.| self | $this |
|---|---|
| The “self” command can be used as a static function. | The $this command cannot be used as a static function. |
| Self:: is used to access class variables and other methods | The $this-> is used to access class variables and methods within. |
| It does not need an instantiated object. | It does need an instantiated object. |
| MySQL | MySQLi |
|---|---|
| This extension was added in version 2.0 of PHP and deprecated with PHP 5.5.0. | Added in PHP 5.5 and is capable to work on MYSQL 4.1.3 or above. |
| No support for prepared statements. | Supports prepared statements. |
| Offers procedural interface. | Offers procedural interface as well as object-oriented interface. |
| No support for the stored procedure. | Supports store procedure. |
| Lags with security and other special features. | Users will receive here better security and advanced debugging. |
| Only SQL queries handled transactions. | It supports API transaction. |
Note: PHP’s easy to learn algorithm combined with its data semantics makes it a very high-functioning language. Our list of PHP interview questions will help you in understanding the core elements of PHP while giving you clarity on the subject.
Top 10 PHP Interview Questions
Here you will find the list of Top PHP interview questions, which were written under the supervision of industry experts. These are the most common questions and usually asked in every interview for the role of the PHP Developers.
- What are Design Patterns in PHP?
- What is the difference between abstract class & interface in PHP.
- What is traits & how it can we used?
- What is the use of .htaccess file?
- What is the difference between MyISAM and InnoDB?
- What is the difference between Public Private and Protected?
- What is Constructor and Destructor?
- What is final class and final method in PHP?
- What is a static member function?
- What is function Overloading and Overriding in PHP?