PHP do while loop : on reaching the control to do statement, the program proceeds to evaluated the body of the loop first. At the end of the loop, the test-condition in the while statement is evaluated,so it is categorized as post tested loop.The basic format of do while() statement is:
do{
body of the loop
}while(test-conditon);
For practice some example are given below with question. So try to understand them.
Question:-write a program to print “welcome” five times on browser using do while()
pro1.php
<?php
$i=1;
do
{
echo “welcome”.”<br>”;
$i++;
}while($i<=10);
?>
Question:-write a program to enter a number and check number is palindrome or not.
pro2.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$cp=$number;
$mod=0;
$rev=0;
do{
$mod=$number%10;
$rev=$rev*10+$mod;
$number=(int)($number/10);
}while($number>0);
if($cp==$rev)
$msg=”Palindrome”;
else
$msg=”Not Palindrome”;
}
?>
<form action=”” method=”post”>
Enter Number<input type=”text” name=”t1″><br>
Reverse<input type=”text” value=”<?php echo $rev;?>”><br>
<input type=”submit” name=”b1″ value=”Reverse”>
</form>
Question:-write a program to enter a number and check entered number is Armstrong or Not (153 is a Armstrong number).
pro3.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$cp=$number;
$digit=0;
$cube_plus=0;
do{
$digit=$number%10;
$cube_plus=$cube_plus+($digit*$digit*$digit);
$number=(int)($number/10);
}while($number>0);
if($cube_plus==$cp)
$msg=”Armstrong”;
else
$msg=”Not Armstrong”;
}
?>
<form action=”” method=”post”>
Enter Number<input type=”text” name=”t1″><br>
Status<input type=”text” value=”<?php echo $msg;?>”><br>
<input type=”submit” name=”b1″ value=”Check”>
</form>
Question:-write a program to enter a number and check entered number is prime or not
pro4.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$i=2;
$h=(int)($number/2);
do{
if($number%$i==0)
break;
$i++;
}while($i<=$h);
if($i>$h)
$msg=”Prime”;
else
$msg=”Not Prime”;
}
?>
<form action=”” method=”post”>
Enter Number<input type=”text” name=”t1″><br>
Status<input type=”text” value=”<?php echo $msg;?>”><br>
<input type=”submit” name=”b1″ value=”Check”>
</form>
Second method for prime number check
pro5.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$flag=0;
$i=2;
$h=(int)($number/2);
do{
if($number%$i==0)
{
$flag=1;
break;
}
$i++;
}while($i<=$h);
if($flag==0)
$msg=”Prime”;
else
$msg=”Not Prime”;
}
?>
<form action=”” method=”post”>
Enter Number<input type=”text” name=”t1″><br>
Status<input type=”text” value=”<?php echo $msg;?>”><br>
<input type=”submit” name=”b1″ value=”Check”>
</form>
Question:-write a program to enter a number and calculate the factorial of entered number.
pro6.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$i=1;
$fact=1;
do{
$fact=$fact*$i;
$i++;
}while($i<=$number);
}
?>
<form action=”” method=”post”>
Enter Number(1-16)<input type=”text” name=”t1″><br>
Factorial<input type=”text” value=”<?php echo $fact;?>”><br>
<input type=”submit” name=”b1″ value=”Check”>
</form>
Second method of factorial calcution.
pro7.php
<?php
if(isset($_POST[‘b1’]))
{
$number=$_POST[‘t1’];
$fact=1;
do{
$fact=$fact*$number;
$number–;
}while($number>=1);
}
?>
<form action=”” method=”post”>
Enter Number(1-16)<input type=”text” name=”t1″><br>
Factorial<input type=”text” value=”<?php echo $fact;?>”><br>
<input type=”submit” name=”b1″ value=”Check”>
</form>