PHP while Loop Guide with Syntax and Examples

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Understand the while loop in PHP for repeated execution based on conditions. Includes syntax, examples, and tips to write cleaner looping logic in PHP.

🔁 PHP `while` Loop

The while loop is one of the simplest and most commonly used loops in PHP. It allows you to run a block of code as long as a specified condition is true.

🧠 How it Works

The basic syntax of a while loop is:

while (condition) {
    // Code to execute as long as condition is true
}

Before each iteration (loop cycle), PHP checks the condition.
If the condition is true, the code inside the loop runs.
Once the condition becomes false, the loop stops.
If the condition is false from the start, the loop will not run at all.

🔄 Alternate Syntax

You can also use an alternate form, especially useful in templates or HTML-heavy code:

while (condition):
    // Code to execute
endwhile;

✅ Example 1: Counting from 1 to 10

<?php
$i = 1;

while ($i <= 10) {
    echo $i . " ";
    $i++;  // Increases $i by 1 each time
}
?>

Output:

1 2 3 4 5 6 7 8 9 10

👉 In this example:

The loop starts with $i = 1.
It runs as long as $i <= 10.
After each loop, $i increases by 1 using $i++.

✅ Example 2: Using Alternate Syntax

<?php
$i = 1;

while ($i <= 10):
    echo $i . " ";
    $i++;
endwhile;
?>

This gives the same output as Example 1, just with a different style of writing.

✅ Example 3: Inside an HTML Page

<!DOCTYPE html>
<html lang="en">
<head>
    <title>PHP - While Loop Example</title>
</head>
<body>

<?php
$x = 1;

while ($x <= 5) {
    echo "The number is: $x <br>";
    $x++;
}
?>

</body>
</html>

Output in browser:

The number is: 1
The number is: 2
The number is: 3
The number is: 4
The number is: 5

📝 Tips

Always make sure your condition will eventually become false. Otherwise, you’ll create an infinite loop that never stops.
The loop variable (like $i or $x) usually gets updated inside the loop to avoid infinite looping.
Use . to concatenate (join) strings and variables, like in echo $i . " ";.