How to print div or rectangle shape by input value

[avinashd]

I am new in php. i want to create a program with input fields as width, height etc. where user input their value and display output as total area, I already finished till here, but i also need a rectangle or div shape as entered input value(width and height). shape should be change according to input values, I tried but could not succeed, can someone please guide me how to do it?

here it is my code, although it is very poor coding, still learning.

<?php

if(!isset($_POST['submit'])){

?>
<form method="post"action="<?php echo $_SERVER['PHP_SELF'];?>">
<h2>Please enter rectangle value</h2>
<p>Enter width value
<input type="text"name="w"/></p>
<p>Enter height value
<input type="text"name="h"/></p>

<p><input type="submit"name="submit"value="Submit"/>
<input type="reset"name="reset"value="Reset"/></p>
</form>
<?php
}else{
$w=$_POST['w'];
$h=$_POST['h'];

if(empty($_POST['w'])|| empty($_POST['h'])){
    echo"please enter value<br/>";
    }
    elseif(!ctype_digit($w)|| (!ctype_digit($h))){
    echo"value must be integer<br/>";
    }
    else
    {
        $w=$_POST['w'];
        $h=$_POST['h'];
    }
    echo "Total area is ".calc($w,$h);
        
    }   

    $w=0;
    $h=0;
    function calc($w,$h){
        $area=$w*$h;
        if($w==$h){
        echo"It is a square<br/>";
    }else{
        echo"It is a rectangle<br/>";
    }
        return $area;
    }
    ?>

[Ch0cu3r]

Use the style attribute to apply the width and height of the div

<div style="width:<?php echo $w; ?>px;height:<?php echo $h; ?>px;background-color:red;border:1px solid #000;"></div>

Edited October 3, 2015 by Ch0cu3r

[QuickOldCar]

You want to define the default $w and $h variable above, as they are now are rewriting the POST values

<?php
$w=0;
$h=0;
if(!isset($_POST['submit'])){

?>
<form method="post"action="<?php echo $_SERVER['PHP_SELF'];?>">
<h2>Please enter rectangle value</h2>
<p>Enter width value
<input type="text"name="w"/></p>
<p>Enter height value
<input type="text"name="h"/></p>

<p><input type="submit"name="submit"value="Submit"/>
<input type="reset"name="reset"value="Reset"/></p>
</form>
<?php
}else{

if(empty($_POST['w'])|| empty($_POST['h'])){
    echo"please enter value<br/>";
    }
    elseif(!ctype_digit($w)|| (!ctype_digit($h))){
    echo"value must be integer<br/>";
    }
    else
    {
        $w=$_POST['w'];
        $h=$_POST['h'];
    }
    echo "Total area is ".calc($w,$h);
        
    }   

 
    function calc($w,$h){
        $area=$w*$h;
        if($w==$h){
        echo"It is a square<br/>";
    }else{
        echo"It is a rectangle<br/>";
    }
        return $area;
    }
    ?>
<div style="width:<?php echo $w;?>px;height:<?php echo $h;?>px;background-color:red;border:1px solid #000;"></div>

Edited October 6, 2015 by QuickOldCar