The while loop in PHP executes a block of code repeatedly as long as a specified condition remains true. It is useful when the number of iterations is unknown in advance.
Syntax of a PHP While Loop
<?php
while (condition) {
// Code to be executed
}
?>
📝 Example 1: Simple While Loop
Prints numbers from 1 to 5.
<?php
$i = 1;
while ($i <= 5) {
echo "Number: $i <br>";
$i++;
}
?>
📝 Example 2: While Loop with Decrement
Prints numbers from 5 to 1.
<?php
$i = 5;
while ($i >= 1) {
echo "Countdown: $i <br>";
$i--;
}
?>
📝 Example 3: While Loop with User Input
Keep asking for user input until they enter "stop" (Assuming input is simulated).
<?php
$input = "";
while ($input != "stop") {
$input = readline("Enter something (type 'stop' to exit): ");
echo "You entered: $input <br>";
}
?>
🎯 When to Use a While Loop?
- When the number of iterations is unknown.
- When continuously checking for a condition.
- For reading data until the end of a file or user input.
📝 Practice Time!
Modify the examples above and experiment with different conditions to understand how while loops work.