The do..while statement will always execute the block of code once,it will then check the condition,and repeat the loop while the condition is true,that means do while is exit control loop the following diagram represent exit control loop.
<?php
do
{
code to be executed
increment & decrement
}while(condition);
?>
<?php
$a=1;
do
{
$a++;
echo $a."
";
$a++;
}while($a<=5);
?>
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