PHP Interview Questions - A Comprehensive Guideline

Key Topics Covered:

PHP Basics

• What is PHP and what are its main features?
• How do you install PHP on different operating systems?
• Explain the difference between echo and print.

Syntax and Variables

• How do you declare and use variables in PHP?
• What are data types in PHP and how are they used?
• Explain variable scope and the difference between local and global variables.

Control Structures

• Describe the use of if, else, and elseif statements.
• How do switch statements work in PHP?
• What are the different types of loops in PHP and how do you use them?

Functions

• How do you define and call a function in PHP?
• What are anonymous functions and closures?
• Explain the concept of variable functions.

Arrays

• How do you create and manipulate arrays in PHP?
• What are associative arrays and how do they differ from indexed arrays?
• Describe array functions like array_merge, array_diff, and array_slice.

Object-Oriented Programming (OOP)

• What are classes and objects in PHP?
• Explain inheritance and how it is implemented in PHP.
• What are interfaces and traits, and how are they used?

File Handling

• How do you read from and write to a file in PHP?
• Explain the use of file handling functions like fopen, fread, and fwrite.
• What are the security considerations when handling files in PHP?

Error Handling

• How does PHP handle errors and exceptions?
• What are the different types of errors in PHP?
• How do you use try, catch, and finally blocks?

Database Integration

• How do you connect to a MySQL database using PHP?
• Explain the use of PDO (PHP Data Objects) for database operations.
• Describe common database operations like SELECT, INSERT, UPDATE, and DELETE.

Security

• What are common security issues in PHP and how do you mitigate them?
• Explain SQL injection and how to prevent it.
• How do you handle XSS (Cross-Site Scripting) and CSRF (Cross-Site Request Forgery)?

PHP Frameworks

• What are PHP frameworks and why are they used?
• Describe popular PHP frameworks like Laravel, Symfony, and CodeIgniter.
• How do you choose the right framework for your project?

Practice Makes Perfect

Our guide includes not just questions, but also detailed answers and explanations to help you understand the concepts thoroughly. Practice with real-world scenarios and coding exercises to boost your confidence.