PHP Loops MCQ Questions and Answers

1. Which of these is a loop structure in PHP?

a) if

b) while

c) echo

d) isset

Answer:

b) while

Explanation:

The while loop is a loop structure in PHP that executes a block of code as long as the specified condition is true.

2. What is the syntax of a for loop in PHP?

a) for (init; condition; increment) { code to be executed; }

b) for (condition; init; increment) { code to be executed; }

c) for { init; condition; increment } (code to be executed)

d) for (init, condition, increment) { code to be executed; }

Answer:

a) for (init; condition; increment) { code to be executed; }

Explanation:

The correct syntax for a for loop in PHP is for (init; condition; increment) { code to be executed; }

3. Which loop will execute the code block at least once, before checking the condition in PHP?

a) while loop

b) do-while loop

c) for loop

d) foreach loop

Answer:

b) do-while loop

Explanation:

The do-while loop will execute its code block once before checking the condition at the end of the loop.

4. How do you break out of a loop in PHP?

a) exit

b) return

c) break

d) continue

Answer:

c) break

Explanation:

The break statement is used to break out of a loop in PHP.

5. What is the purpose of the continue statement in a loop in PHP?

a) Stops the loop

b) Skips the current iteration and continues with the next iteration

c) Continues execution outside of the loop

d) Restarts the loop

Answer:

b) Skips the current iteration and continues with the next iteration

Explanation:

The continue statement skips the rest of the current loop iteration and continues with the next iteration.

6. What type of loop is the foreach loop in PHP?

a) Conditional loop

b) Count-controlled loop

c) Infinite loop

d) Iterative loop over arrays

Answer:

d) Iterative loop over arrays

Explanation:

The foreach loop is used to iterate over arrays in PHP.

7. What does the following PHP code do? for ($i = 0; $i < 10; $i++) { echo $i; }

a) Prints numbers from 0 to 9

b) Prints numbers from 1 to 10

c) Results in an infinite loop

d) Throws an error

Answer:

a) Prints numbers from 0 to 9

Explanation:

The for loop initializes $i to 0 and runs until $i is less than 10, incrementing $i in each iteration.

8. How many expressions are there in a typical for loop declaration in PHP?

a) One

b) Two

c) Three

d) Four

Answer:

c) Three

Explanation:

A typical for loop in PHP contains three expressions: initialization, condition, and increment.

9. Which loop is best suited for iterating over an associative array in PHP?

a) while loop

b) do-while loop

c) for loop

d) foreach loop

Answer:

d) foreach loop

Explanation:

The foreach loop is best suited for iterating over associative arrays in PHP.

10. How do you create an infinite loop in PHP?

a) while (true) { code to be executed; }

b) for (;;) { code to be executed; }

c) Both a) and b)

d) Using the infinite() function

Answer:

c) Both a) and b)

Explanation:

Both while (true) and for (;;) create infinite loops in PHP.

11. What is the initial value of the loop variable in a typical PHP for loop?

a) 0

b) 1

c) NULL

d) Depends on the loop

Answer:

d) Depends on the loop

Explanation:

The initial value of the loop variable in a for loop depends on what the programmer sets it to.

12. In a nested loop, what does the inner loop do?

a) Executes once for each iteration of the outer loop

b) Replaces the outer loop

c) Is ignored

d) Causes an error

Answer:

a) Executes once for each iteration of the outer loop

Explanation:

In a nested loop, the inner loop completes all its iterations for each single iteration of the outer loop.

13. How does the while loop in PHP differ from the do-while loop?

a) The while loop checks the condition before executing the code block, the do-while loop checks it after

b) There is no difference

c) The while loop is faster

d) The do-while loop can't be used with arrays

Answer:

a) The while loop checks the condition before executing the code block, the do-while loop checks it after

Explanation:

The main difference between while and do-while loops is that while checks the condition before executing the loop body, whereas do-while checks it after.

14. What will happen if the increment statement is omitted in a for loop in PHP?

a) The loop will not execute

b) The loop may become an infinite loop

c) The loop will execute once

d) The loop will execute normally

Answer:

b) The loop may become an infinite loop

Explanation:

Omitting the increment statement in a for loop can result in an infinite loop if the loop condition is always true.

15. Can the foreach loop be used with both arrays and objects in PHP?

a) Yes

b) No

c) Only with arrays

d) Only with objects

Answer:

a) Yes

Explanation:

The foreach loop in PHP can be used to iterate over both arrays and objects.