While loop execution model in C Sharp (C#) - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the basic structure of a while loop in C#?

A while loop repeatedly executes a block of code as long as its condition is true. The structure is:<br>

while (condition) {<br>  // code to repeat<br>}

beginner

When does the condition in a while loop get evaluated?

The condition is checked before each iteration. If the condition is false at the start, the loop body does not run at all.

intermediate

What happens if the while loop condition never becomes false?

The loop runs forever, causing an infinite loop. This can freeze or crash the program if not stopped.

intermediate

How can you safely exit a while loop before the condition becomes false?

You can use the break statement inside the loop to exit immediately when a certain condition is met.

intermediate

Explain the difference between while and do-while loops.

while checks the condition before running the loop body, so it may run zero times.<br>do-while runs the loop body first, then checks the condition, so it runs at least once.

When is the condition in a while loop checked?

A After each iteration

B Before each iteration

C Only once before the loop starts

D Only once after the loop ends

The while loop checks its condition before every iteration to decide whether to run the loop body.

What happens if the while loop condition is false at the start?

A The program crashes

B The loop body runs once

C The loop runs infinitely

D The loop body does not run at all

If the condition is false initially, the while loop skips the body completely.

Which statement can be used to exit a while loop early?

A continue

B exit

C break

D return

The break statement immediately stops the loop and continues with the code after it.

What is a risk of a while loop if the condition never becomes false?

A An infinite loop occurs

B The loop runs once

C The loop runs zero times

D The loop throws an error

If the condition never becomes false, the while loop runs forever, causing an infinite loop.

How does a do-while loop differ from a while loop?

A It runs the loop body at least once before checking the condition

B It checks the condition before running the loop body

C It cannot run infinitely

D It does not use a condition

do-while loops run the loop body first, then check the condition, so they always run at least once.

Describe how a while loop executes step-by-step in C#.

Think about what happens before and after each time the loop runs.

Explain why it is important to update variables inside a while loop.

Consider what happens if the condition never changes.