I am working on a project where I need to calculate some numbers in html table with javascript. The user can add as much numbers as they need and once they click a button, they'll need to see the end sum. I would like to know how I can do that with javascript, you can find the code below:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ".dtd">
<html xmlns="" >
<head>
<title>Javascript Calculator</title>
<SCRIPT language="javascript">
function Calculate()
{
}
function addRow()
{
var table = document.getElementById('table');
var button = document.getElementsByTagName('input')[0];
button.onclick = function() {
var clone = table.rows[table.rows.length - 2].cloneNode(true);
clone.cells[0].firstChild.data =
clone.cells[0].firstChild.data.replace(/(\d+):/,function(str,g1) {
return (+g1 + 1) + ':';
});
table.tBodies[0].appendChild(clone);
};
}
</SCRIPT>
</head>
<input type=button value='Add Row' onclick="addRow()" />
<br /><br />
<table cellspacing=0 cellpadding=4 id="table">
<tbody>
<tr><td>Number 1:</td><td><input value=20 style="width:30px" type=text maxlength=2/></td></tr>
<tr><td>Number 2:</td><td><input value=25 style="width:30px" type=text maxlength=2/></td></tr>
</tbody>
<tfoot>
<tr><td style="border-top:solid 1px black;border-bottom:solid 1px black;">Sum:</td><td style="border-top:solid 1px black;border-bottom:solid 1px black;"><div>45</div></td></tr>
</tfoot>
</table>
<input type=button value='Recalculate Sum' onclick="Calculate()" />
</body>
</html>
Any idea how I can solve this? Thanks in advance, Laziale
I am working on a project where I need to calculate some numbers in html table with javascript. The user can add as much numbers as they need and once they click a button, they'll need to see the end sum. I would like to know how I can do that with javascript, you can find the code below:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3/1999/xhtml" >
<head>
<title>Javascript Calculator</title>
<SCRIPT language="javascript">
function Calculate()
{
}
function addRow()
{
var table = document.getElementById('table');
var button = document.getElementsByTagName('input')[0];
button.onclick = function() {
var clone = table.rows[table.rows.length - 2].cloneNode(true);
clone.cells[0].firstChild.data =
clone.cells[0].firstChild.data.replace(/(\d+):/,function(str,g1) {
return (+g1 + 1) + ':';
});
table.tBodies[0].appendChild(clone);
};
}
</SCRIPT>
</head>
<input type=button value='Add Row' onclick="addRow()" />
<br /><br />
<table cellspacing=0 cellpadding=4 id="table">
<tbody>
<tr><td>Number 1:</td><td><input value=20 style="width:30px" type=text maxlength=2/></td></tr>
<tr><td>Number 2:</td><td><input value=25 style="width:30px" type=text maxlength=2/></td></tr>
</tbody>
<tfoot>
<tr><td style="border-top:solid 1px black;border-bottom:solid 1px black;">Sum:</td><td style="border-top:solid 1px black;border-bottom:solid 1px black;"><div>45</div></td></tr>
</tfoot>
</table>
<input type=button value='Recalculate Sum' onclick="Calculate()" />
</body>
</html>
Any idea how I can solve this? Thanks in advance, Laziale
Share Improve this question asked Jan 13, 2012 at 17:16 LazialeLaziale 8,22548 gold badges155 silver badges271 bronze badges2 Answers
Reset to default 2You can loop through each input element in the table and grab the value.
function Calculate() {
var table = document.getElementById('table');
var items = table.getElementsByTagName('input');
var sum = 0;
for(var i=0; i<items.length; i++)
sum += parseInt(items[i].value);
var output = document.getElementById('sum');
output.innerHTML = sum;
}
demo
The only change I made to the HTML was giving an ID to the output div.
<div id="sum">45</div>
use this to grab the inputs
var inputs = document.getElementsByTagName('input');
this will grab all the inputs's, not just 'text' inputs, so you'll want to use something like this in the loop
if(inputs[i].type == 'text')
total = total + parseInt(inputs[i].value);
and set the value like this
document.getElementById('displaySum').innerHTML = total;