Loops (while statements)

In this lesson you will learn how to repeat work with a while statement in PHP and how to tell it apart from a for statement. This is for anyone searching for "PHP while loop how to use".

A while statement repeats as long as its condition holds. The rule of thumb is to use a for loop when you already know the stopping point and a while loop when you do not. Just remember to update the variable the condition depends on inside the loop.

The sample code repeats while $i is 5 or less, increasing the value by one with $i++; inside the loop. The condition is evaluated at the top of every pass, and the moment it becomes false the loop exits and execution moves on.

A common stumbling block for beginners is forgetting that update and ending up in an infinite loop. When you actually want an endless loop, the standard pattern is while(true) with a break to leave it - worth knowing both.

It shines wherever the number of repetitions cannot be predicted, such as accepting user input continuously or searching until a condition is met. While loops are common in batch jobs and command-line tools too.