PHP technical interview questions and answers are essential for candidates preparing for web development roles. PHP powers millions of websites and content management systems, so companies often evaluate your knowledge of syntax, arrays, sessions, cookies, form handling, OOP concepts, and database connectivity. Popular companies like TCS, Wipro, Infosys, Capgemini, Cognizant, and Accenture regularly include PHP questions in coding rounds and technical interviews. This guide explains the most frequently asked PHP interview questions with simple examples and clear definitions. Whether you are a fresher preparing for campus placements or an experienced developer, these questions will help you understand PHP concepts better. You can also download PHP interview PDFs and practice mock questions for better preparation.
2. whats the difference between include and require?
Its how they handle failures. If the file is not found by require(), it will cause a fatal error and halt the execution of the script. If the file is not found by include(), a warning will be issued, but execution will continue.
3. Would I use print "$a dollars" or "{$a} dollars" to print out the amount of dollars in this example?
In this example it wouldnt matter, since the variable is all by itself, but if you were to print something like "{$a},000,000 mln dollars", then you definitely need to use the braces.
4. How do you define a constant?
Via define() directive, like define ("MYCONSTANT", 100);
5. How do you pass a variable by value?
Just like in C++, put an ampersand in front of it, like $a = &$b
6. Will comparison of string "10" and integer 11 work in PHP?
Yes, internally PHP will cast everything to the integer type, so numbers 10 and 11 will be compared.
7. When are you supposed to use endif to end the conditional statement?
When the original if was followed by : and then the code block without braces.
8. Explain the ternary conditional operator in PHP?
Expression preceding the ? is evaluated, if Its true, then the expression preceding the : is executed, otherwise, the expression following : is executed.
9. How do I find out the number of parameters passed into function?
func_num_args() function returns the number of parameters passed in.
10. If the variable $a is equal to 5 and variable $b is equal to character a, whats the value of $$b?