Start New Discussion within our UI / UX Design Community

Here we use the eval() function as the backbone of a simple calculator. One table is used for the display. A second table holds the buttons for the keypad. The whole thing forms an attractive looking calculator. To test it, simply paste the code into an editor like notepad and save it as Calculator.htm then run it in your browser.

<!-- experiments with table & button-input  vegaseat  2/13/02 -->
<!-- table, border, cellpadding, cellspacing, input, onClick -->
<!-- uses eval() to do the final calculation -->
<!-- note: eval() traps divide by zero error -->

<html>
<head>

	<title>A Simple Four-Banger</title>
	
</head>
<body>

<form name="calculator">

<!-- form the display to match the keypad -->
<table border="4" cellpadding="1" bordercolor="#FFFFFF" bgcolor="#73B27B" cellspacing="2" width="222">
<tr>
<td>
<input type="text" size="25" length="25" value="" name="ans" style="background:beige;color:black;">
</td>
</tr>
</table>

<!-- form the keypad with buttons in a table -->
<table border="4" cellpadding="2" bordercolor="#FFFFFF" cellspacing="2" width="150" bgcolor="#73B27B">
<tr>
<td align="center">
<input type="button" value="  7  " name="seven" onClick="document.calculator.ans.value+='7'">
</td>
<td align="center">
<input type="button" value="  8  " name="eight" onClick="document.calculator.ans.value+='8'">
</td>
<td align="center">
<input type="button" value="  9  " name="nine" onClick="document.calculator.ans.value+='9'">
</td>
<td align="center">
<input type="button" value="  /  " name="divide" onClick="document.calculator.ans.value+='/'">
</td>
</tr>
<tr>
<td align="center">
<input type="button" value="  4  " name="four" onClick="document.calculator.ans.value+='4'">
</td>
<td align="center">
<input type="button" value="  5  " name="five" onClick="document.calculator.ans.value+='5'">
</td>
<td align="center">
<input type="button" value="  6  " name="six" onClick="document.calculator.ans.value+='6'">
</td>
<td align="center">
<input type="button" value="  *  " name="multiply" onClick="document.calculator.ans.value+='*'">
</td>
</tr>
<tr>
<td align="center">
<input type="button" value="  1  " name="one" onClick="document.calculator.ans.value+='1'">
</td>
<td align="center">
<input type="button" value="  2  " name="two" onClick="document.calculator.ans.value+='2'">
</td>
<td align="center">
<input type="button" value="  3  " name="three" onClick="document.calculator.ans.value+='3'">
</td>
<td align="center">
<input type="button" value="  -  " name="subtract" onClick="document.calculator.ans.value+='-'">
</td>
</tr>
<tr>
<td align="center">
<input type="button" value="  C  " name="clear" onClick="document.calculator.ans.value=''">
</td>
<td align="center">
<input type="button" value="  0  " name="zero" onClick="document.calculator.ans.value+='0'">
</td>
<td align="center">
<input type="button" value="  =  " name="equal" 
  onClick="document.calculator.ans.value=eval(document.calculator.ans.value)">
</td>
<td align="center">
<input type="button" value="  +  " name="add" onClick="document.calculator.ans.value+='+'">
</td>
</tr>
</table>

</form>

</body>
</html>

:) Wow, Its Just Gr8. But I am having a similar HTML calculator in my blogsite ( <URL SNIPPED> ). Please have a look at it. And give your suggestions to improve it.

hello! can you give the code of the 4 basic operation in calculator?
such sa addtion, subtraction, addition and multiplication..

tnx a lot..

I'm very very new to all this, but I'm having fun learning. I like the calculator, is there a way to make it round up to only 2 decimals? Please be very detailed - remember I'm very new.

Thanks

Damn good, I have only one possible idea
calclualtors usually are right justified, the digits extend from the right
so for the input containing the number <input style='text-align:right;' type="text" size="25" length="25" value="" name="ans" style="background:beige;color:black;">

A Simple calculator usng form fileds, have a files number entry one fill for resut allow the user to be able to use +,-,*,/

how will create this type of calculator can u send me or replay

Hi guys This is Rahul
I need some more controls in calc like cancel,enter,backsapce can any one help to me pls.

the only change I think to to make is in the display,
calculators typically fill from right to left as you punch numbers so

<input style='text-align:right;' type="text" size="25" length="25" value="" name="ans" style='text-align:right;background:beige;color:black;'>

hi everyone! can you pls give me the code of the 4 basic operation in calculator in powerbuilder 8.0?
such sa addtion, subtraction, addition and multiplication..

thnx a lot...

not only html, javascript to do the crunching,
innoccuous javascript,
but some users have all javascripting disabled as a security issue.

Hi I would need one decimal also.
However I have edited and got it. But it is also a necessary thing..

Hi, I'm looking for html codes to calculate a date. For example, in excel i can have a date that says 8/06/11. I want to calculate 90 days from that date. in excel the formula would be =A1+90, which will equal 11/04/11.

I have it PHP:

$today = date("Y-m-d");// current date
$tomorrow = strtotime(date("Y-m-d", strtotime($today)) . " +1000 day");
$output = date("Y-m-d", $tomorrow);

I need it in HTML.


please help!!!!!

The article starter has earned a lot of community kudos, and such articles offer a bounty for quality replies.