Solved

How to calculate 3 textbox multiply values in real time?

Posted on 2009-04-05
4
1,258 Views
Last Modified: 2013-12-17
I have aspx page which has 4 textbox.

txtAmount, txtExchangeRate, txtCharges, txtResult

When you input txtAmount, txtExchangeRate, txtCharges, then txtResult will show the calculated result.

e.g. 405 * 0.88 + 20 = result

As there are many rows in that listInput, how can it be done to show the result in real time?
0
Comment
Question by:techques
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
4 Comments
 
LVL 75

Expert Comment

by:Michel Plungjan
ID: 24074769
With straight JS I would do this - I hope this is NOT homework - it is it, next time please start the html and script yourself and ask if you are stuck:


<html>
  <head>
  <title></title>
<script type="text/javascript">
function calc(theForm) {
  var amount = parseFloat(theForm.txtAmount.value)
  if (isNaN(amount)) amount=0;
  var exchangeRate = parseFloat(theForm.txtExchangeRate.value)
  if (isNaN(exchangeRate)) exchangeRate=0;
  var charges = parseFloat(theForm.txtCharges.value)
  if (isNaN(charges)) charges=0;
  var result =  (amount * exchangeRate) + charges
  theForm.txtResults.value=result.toFixed(2);
}
</script>
  </head>
  <body>
<form>
<input type="text" name="txtAmount"       value="" onKeyUp="calc(this.form)" /> *
<input type="text" name="txtExchangeRate" value="" onKeyUp="calc(this.form)" /> +
<input type="text" name="txtCharges"      value="" onKeyUp="calc(this.form)" /> =
<input type="text" name="txtResults"      value="0.00" readonly="readonly" />
</form>
  </body>
</html>

Open in new window

0
 
LVL 6

Assisted Solution

by:havj123
havj123 earned 20 total points
ID: 24074814
Use this

<table>
        <tr>
            <td>
                <input type="text" id="txtAmount" name="txt1" />
                <input type="text" id="txtExchangeRate" name="txt2"/>
                <input type="text" id="txtCharges" onchange="calculate();" name="txt3" />
                <input type="text" id="txtResult" name="txt4"/>
            </td>
        </tr>
    </table>

javascript function:-

<script type="text/javascript">
        function calculate()
        {
            var amt, ex, ch, result;
            amt = document.getElementById("txtAmount").value;
            ex = document.getElementById("txtExchangeRate").value;
            ch = document.getElementById("txtCharges").value;
            result = document.getElementById("txtResult");
           
            if(amt != "" || ex != "" || ch != "" || amt != null || ex != null || ch != null)
            {
                result.value = parseInt(amt*ex)+parseInt(ch);
            }
        }
 </script>

Note: either make txtAmount, txtExchangeRate, txtCharges required or convert empty string to 0.
0
 
LVL 75

Accepted Solution

by:
Michel Plungjan earned 30 total points
ID: 24074845
Alternatively if you need to calculate rows of data, try this:

<html>
  <head>
  <title></title>
<script type="text/javascript">
function calc(theField) {
  var id = theField.name.split('_')[1]; // change this to find the common part of the names
  var theForm = theField.form;
  var amount = parseFloat(theForm.elements["txtAmount_"+id].value)
  if (isNaN(amount)) amount=0;
  var exchangeRate = parseFloat(theForm.elements["txtExchangeRate_"+id].value)
  if (isNaN(exchangeRate)) exchangeRate=0;
  var charges = parseFloat(theForm.elements["txtCharges_"+id].value)
  if (isNaN(charges)) charges=0;
  var result =  (amount * exchangeRate) + charges
  theForm.elements["txtResults_"+id].value=result.toFixed(2);
}
</script>
  </head>
  <body>
    <form>
      <input type="text" name="txtAmount_1"       value="" onKeyUp="calc(this)" /> *
      <input type="text" name="txtExchangeRate_1" value="" onKeyUp="calc(this)" /> +
      <input type="text" name="txtCharges_1"      value="" onKeyUp="calc(this)" /> =
      <input type="text" name="txtResults_1"      value="0.00" readonly="readonly" /><br />
      <input type="text" name="txtAmount_2"       value="" onKeyUp="calc(this)" /> *
      <input type="text" name="txtExchangeRate_2" value="" onKeyUp="calc(this)" /> +
      <input type="text" name="txtCharges_2"      value="" onKeyUp="calc(this)" /> =
      <input type="text" name="txtResults_2"      value="0.00" readonly="readonly" /><br />
    </form>
  </body>
</html>

Open in new window

0
 
LVL 75

Expert Comment

by:Michel Plungjan
ID: 24076604
erm 50 points, split and then an uncommented "B" grade???
0

Featured Post

Forrester Webinar: xMatters Delivers 261% ROI

Guest speaker Dean Davison, Forrester Principal Consultant, explains how a Fortune 500 communication company using xMatters found these results: Achieved a 261% ROI, Experienced $753,280 in net present value benefits over 3 years and Reduced MTTR by 91% for tier 1 incidents.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
Boost your ability to deliver ambitious and competitive web apps by choosing the right JavaScript framework to best suit your project’s needs.
The viewer will learn the basics of jQuery, including how to invoke it on a web page. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery.: (CODE)
The viewer will learn the basics of jQuery including how to code hide show and toggles. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery…

738 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question