One of the most enjoying past time that I would like to spend is to write a program it becomes one of my favorite hobbies during my college days. In this article I would like to share with you one of the most common programming problems in PHP how to write a simple calculator using radio buttons in PHP. Some of us think this kind of problem is very simple yes they are for some people who has already learned some experience in PHP programming but for some that are new in PHP problem it can gives us some headache if you don't how to figure it out. Our program will ask the user to enter two number in our text field and then our program will provide four radio buttons addition, subtraction, multiplication and division. Once the user select for example addition and click the solve button it will display the sum of the two numbers. I also added a clear button that enables the user to clear the text field and allows them to enter new values.
The challenge that I face in writing this program is that I want to keep or retain the value of my selection radio button for example the addition radio button I want to retain its value after i click the solve button. In this program you will know how to accomplish such task with each. I have a great time writing this program I hope you will find my work useful in your quest in learning PHP programming.
If you have some questions please send me an email at jakerpomperada@yahoo.com and jakerpomperada@gmail.com.
People here in the Philippines who wish to contact me can reach me at my mobile number 09173084360.
Sample Output of Our Program
Program Listing
<head>
<?php
error_reporting(0);
$first = $_REQUEST['first'];
$second= $_REQUEST['second'];
$first2 = (int)$first;
$second2 = (int)$second;
if (isset($_REQUEST['solve'])) {
$op = $_REQUEST['op'];
if ($op == 'add') {
$add = $first2 + $second2;
$title .="The sum of ".$first2. " and " .$second2.
" is " .$add.".";
}
if ($op == 'subtract') {
$subtract = $first2 - $second2;
$title .="The difference between ".$first2. " and " .$second2.
" is " .$subtract.".";
$op = ' checked="checked"';
}
if ($op == 'times') {
$product = $first2 * $second2;
$title .="The product of ".$first2. " and " .$second2.
" is " .$product.".";
}
if ($op == 'divide') {
$quotient = $first2 / $second2;
$title .="The quotient of ".$first2. " and " .$second2.
" is " .$quotient.".";
}
}
if(isset($_REQUEST['clear'])) {
$first2 = " ";
$second2 = " ";
$result= " ";
}
?>
<title>Calculator in PHP</title>
</head>
<style>
body {
background-color: lightgreen;
font-family:arial;
font-style:bold;
font-size:22px;
font-family:arial;
color:blue;
}
input
{
-moz-border-radius: 15px;
border-radius: 15px;
border:solid 3px BLUE;
padding:8px;
}
input {
display: table-cell;
}
label{
display: table-cell;
text-align: justify;
}
div.row{
display:table-row;
}
/***FIRST STYLE THE BUTTON***/
button#gobutton{
cursor:pointer; /*forces the cursor to change to a hand when the button is hovered*/
padding:5px 25px; /*add some padding to the inside of the button*/
background:white; /*the colour of the button*/
border:1px solid #33842a; /*required or the default border for the browser will appear*/
/*give the button curved corners, alter the size as required*/
-moz-border-radius: 6px;
-webkit-border-radius: 6px;
border-radius: 6px;
/*give the button a drop shadow*/
-webkit-box-shadow: 0 0 4px rgba(0,0,0, .75);
-moz-box-shadow: 0 0 4px rgba(0,0,0, .75);
box-shadow: 0 0 4px rgba(0,0,0, .75);
/*style the text*/
color:blue;
font-size:1.1em;
}
/***NOW STYLE THE BUTTON'S HOVER AND FOCUS STATES***/
button#gobutton:hover, button#gobutton:focus{
background-color :brown; /*make the background a little darker*/
/*reduce the drop shadow size to give a pushed button effect*/
-webkit-box-shadow: 0 0 1px rgba(0,0,0, .75);
-moz-box-shadow: 0 0 1px rgba(0,0,0, .75);
box-shadow: 0 0 1px rgba(0,0,0, .75);
}
</style>
<body>
<div style='width:800px;margin:auto'>
<form>
<H2> Calculator in PHP </h2>
<div class="row"><label> FIRST VALUE
<input type="text" id="first" name="first" placeholder="enter first value"
value="<?php echo $first; ?>" autofocus required size=10></label></div><br>
<div class="row"> <label> SECOND VALUE
<input type="text" id="second" name="second" placeholder="enter second value"
value="<?php echo $second; ?>" autofocus required size=10></label> </div>
<br>
<input type="radio" name="op" value="add" <?php if($_REQUEST['op'] == "add") echo "checked"; ?>>ADDITION
<input type="radio" name="op" value="subtract" <?php if($_REQUEST['op'] == "subtract") echo "checked"; ?> >SUBTRACTION
<input type="radio" name="op" value="times" <?php if($_REQUEST['op'] == "times") echo "checked"; ?>>MULTIPLICATION
<input type="radio" name="op" value="divide" <?php if($_REQUEST['op'] == "divide") echo "checked"; ?>>DIVISION
<br><br>
<button id="gobutton" type="submit" name="solve" id="solve" value="answer"
title="Click here to find the result.">Solve</button>
<button id="gobutton" type="submit" name="clear" id="clear" value="answer"
title="Click here to clear text fields.">Clear</button>
</form>
<br>
<?php
echo $title;
?>
</body> </div>
</html>
