While Loop in PHP
PHP has support for both:
- While loop - a pre-test loop, like the for loop. However, while loops are a condition-controlled loop versus a count-controlled loop which the for loop is.
- Do ... While loop - a post-test loop, e.g. test condition is at end of loop. This means the loop will always run at least once.
Example: Simple while loop
<?php
$y = 1;
while ($x < 6)
{
$y = $y + 2;
echo "<p>x equals $x, y equals $y.</p>";
$x++;
}
?>
Output:
x equals 1, y equals 3.
x equals 2, y equals 5.
x equals 3, y equals 7.
x equals 4, y equals 9.
x equals 5, y equals 11.
Example: Simple while loop
<?php
$x=0;
while ($x < 10)
{
if ($x % 2 == 0)
echo "<p>$x is an even number.</p>";
$x++;
}
?>
Example: Do .. While loop
<?
$x=1;
do
{
echo "<p>x is equal to $x.</p>";
$x++;
} while ($x<5);
?>
Output:
x is equal to 1.
x is equal to 2.
x is equal to 3.
x is equal to 4.