Le 7/1/10 6:19 PM, Kevin Davis a écrit :
Hi there,
I have a bunch of text boxes that I want to add up and have another
text box that would show the total each time there is a number. Is
there a way to do that in JavaScript??
Yes, of course.
In each input tag you add an attribute 'onchange' with a JS function to
do the addition.
Take care that imput's value are strings
(that can't be mathematically added)
Better if this function can admit the coma in decimal separator.
About numbers in JS :
<
http://jibbering.com/faq/#numbers>
Non documented example :
<script type="text/javascript">
function total() {
var f = document.forms[0],
n = f.length - 3,
sum = 0,
numJS = function(num) {
return num.replace(/,(\d{1,2})$/,'.$1')*1; };
while(n--)
if ( f[n].type == 'text' &&
f[n].value.length > 0 )
if( !!numJS(f[n].value)/2 ) sum += numJS(f[n].value);
else {
alert('You didn\'t enter a number/n'+
'thousand separator not allowed');
sum = 'error';
setTimeout( function() {
f[n].focus();
f[n].select();
},0);
break
}
f['result'].value = sum;
return (sum == 'error');
}
</script>
</head>
<body>
<form action="test.htm" onsubmit="return total()">
<p>price: <input onchange="total()"></p>
<p>price: <input onchange="total()"></p>
<p>price: <input onchange="total()"></p>
<p>price: <input onchange="total()"></p>
<p>price: <input onchange="total()"></p>
<hr>
<p>total: <input name="result"></p>
<p style="border:1px solid;text-align:right">
<input type="reset"> <input type="submit">
</p>
</form>
