# A four function calculator (HTML)

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>

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

<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>``````

this is alsome!

wow.. its great...

how can I come up with the if and else, for loop, cases with 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?

tnx a lot..

using vb6

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

almostbob 866

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;">`

Wow! This is really awesome!!. .

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.

ablitz -5

thanx for sharing:)

almostbob 866

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?

thnx a lot...

Awesome! can we make this calculator only with the help of html?

almostbob 866

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.

Arkinder 93

Regards
Arkinder

Excellent. I'm trying to learn html this has helped me a lot. Many thanks

Here is how I would approach your calculator problem:

e.g., http://www.daniweb.com/code/snippet216407.html

2) use MobiOne Design Center to paint a calculator UI.
2a) Use custom button components for the numbers and functions. Create an initial button for the numbers and the copy/paste it 8 more times and change it's text for the appropriate number, 0-9
2b) Include an input field component for presenting the current value

3) run the design in the Test Center iPhone emulator to confirm the UI appears the way you want it to

4) you'll have to write javascript for the button actions
See #1 above for example code and inspiration :)
You can use the Test Center to view and edit the HTML, JS, or CSS files that make up your calculator webapp.

Note, MobiOne does not yet protect customizations of the generated code from a design. Therefore be extra careful not to overwrite your custom js in #3. Currently I put my custom css and js in completely separate files.

Good luck.

MidiMagic 579

HTML needs a script to do any math or display any numbers from a data source. Used alone, HTML can't do anything but control how a web page is displayed.

not run plz help

I also make calculator in java script. When i developed my calculator in javascript I had to write many function. Your code is very simple and no need to use javascript. I also checked it on browser, worked well.

Wow is's so so simple. I was thinking about DOM tree, innerHTML so on so on.

OHHH SOME!!!

wow html can do maths? i taught only java script could do it!

diafol

Please guys. Leave this thread alone unless you have a question or an improvement. If you wish to say thank you, kindly give the contributors a +1 or some positive reputation instead of leaving a comment as that only serves to push this very old post to the top of the "current" list. Posters who post drivel will probably find that they will be downvoted by the community. Thank you.

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