Top 53+ PHP Interview Questions and Answers in 2023 Updated

A PHP file is a text file that contains PHP code, typically with a .PHP extension. It is an integral part of building dynamic web pages and applications. A PHP file can include a combination of HTML, CSS, JavaScript, and PHP code. This versatility enables developers to integrate dynamic functionalities with the presentation layer.

This function is used to define and pull out the values of the constants easily. For example, user-defined functions in PHP can be defined in uppercase but later referred to in lowercase, and it would still function normally. They should also be able to explain how they’d use serverless architectures to create efficient and reliable applications. Be prepared to discuss your experience with deploying and managing websites on cloud hosting platforms.

What are the popular Content Management Systems (CMS) in PHP?

PHP enables dynamic content creation, database connectivity, and server-side scripting. With its extensive community and rich set of features, it has become one of the most popular languages for building dynamic websites and web applications. It is possible to generate HTML through PHP scripts, and it is possible to pass pieces of information from HTML to PHP.

No direct interaction is possible between JS and PHP because, while the former is a client-side language, the latter is a server-side language. An indirect interaction between the two leading programming languages can happen using exchanging variables. Constructors and destructors in PHP are special types of functions, which are automatically called when a PHP class object is created and destroyed, respectively. Magic methods are member functions that are available to all the instances of a class. Magic methods always start with ‘__’, for example, __construct().

What is the actually used PHP version?

$_ENV is an associative array of variables sent to the current PHP script via the environment method. The session_unregister() function unregister a global variable from the current session and the session_unset() function frees all session variables. The function mysqli_num_rows() returns the number of rows in a result set.

Refactoring code is an important part of any software development job, and it can be tricky to do correctly. Interviewers want to know that you understand the importance of refactoring and that you have experience doing it. They may also be interested in hearing your process for refactoring code and how you assess the effectiveness of the changes you make. The interviewer wants to know that you have the skills to work efficiently and effectively on their team.

How does PHP interact with Javascript?

The variables and their order listed in the $_REQUEST array is defined in the PHP variables_order configuration directive. When a variable’s data type is converted explicitly by the user, it is known as typecasting. The PHP programming language doesn’t support explicit type definition in variable declaration. Hence, the data type of the variable is determined by the context in which the variable is used. The attacker can disclose the content of the file attacked using the path traversal outside the root directory of a web server or application.

They allow developers to define and set initial values for the object’s properties or perform other initialization logic. By using constructors, the object can be properly configured and ready to be utilized immediately. JavaScript is a client-side programming language, while PHP is a server-side scripting language. PHP has the ability to generate JavaScript variables, and this can be executed easily in the browser, thereby making it possible to pass variables to PHP using a simple URL. This question is designed to assess your experience and technical knowledge. They want to know if you have the skills and experience necessary to be successful in the role.

What is PHP?

Dependency Injection (DI) is a design pattern and a programming technique used in software development to achieve loose coupling between components or classes. In DI, the dependencies of a class are not created within the class itself but are provided from the outside, typically through the class constructor or setter methods. This approach promotes modularity, testability, and maintainability by reducing the direct dependencies between components. In PHP, the __get() method is a magic method used for intercepting and handling attempts to read inaccessible or undefined properties within an object. It is automatically called when a property is accessed that is not accessible or does not exist. With __get(), you can define custom logic to handle property access such as returning computed values or retrieving data from alternative sources.

Break and continue statements are two fundamental concepts of programming. A break statement is used to terminate a loop or switch statement immediately. In contrast, a continue statement is used to skip the current iteration of the loop and continue with the next iteration.

$GLOBALS is associative array including references to all variables which are currently defined in the global scope of the script. Require () includes and evaluates a specific file, while require_once () does so only if it has not been included previously. The require_once () statement can be used to include a PHP file in another when you may need to include the called file more than once. So, require_once () is recommended when you want to include a file where you have a lot of functionality. If the function requires () fails to access the file, then it ends with a ‘fatal’ error.

• If the session is not available, it creates and returns new sessions.
• If not, the run-time will raise an error and execution will be halted.
• The header() function is used to send a raw HTTP header to a client.
• This means it will be harder for you to recruit skilled and affordable talent.
• PHP is partly a case sensitive language where the variable names are case-sensitive but function names are not.

PHP arrays can be treated as lists when the keys are used as indices to access elements. In PHP, an abstract class is a class that cannot be instantiated directly https://wizardsdev.com/en/vacancy/middle-php-developer/ and serves as a blueprint for derived classes. Abstract classes may contain abstract methods which are declared but not implemented in the abstract class itself.