total function

[beavenour]

I am looking for some help creating a more universal function out of
this lame attempt at javascript. I have little experience with
javascript and want to be able to universalize this function. So how
do I change this script so that I can call any field or any number of
fields to be totaled? For example - calculate(myfield01, myfield02)
at one total field and calculate(myfield06, myfield08, myfield11) at
another total field instead of creating a whole new function to do
each. Any help or suggestions would be very much apprectated.


<SCRIPT language = JavaScript>
function calculate() {

a = parseInt(document.myform.myfield01.value);
b = parseInt(document.myform.myfield02.value);
c = parseInt(document.myform.myfield03.value);
d = parseInt(document.myform.myfield04.value);

z = Math.round((a + b + c + d)*100)/100;
document.myform.total.value = z;
}
</SCRIPT>

 

[Grant Wagner]

I am looking for some help creating a more universal function out of
this lame attempt at javascript. I have little experience with
javascript and want to be able to universalize this function. So how
do I change this script so that I can call any field or any number of
fields to be totaled? For example - calculate(myfield01, myfield02)
at one total field and calculate(myfield06, myfield08, myfield11) at
another total field instead of creating a whole new function to do
each. Any help or suggestions would be very much apprectated.

<SCRIPT language = JavaScript>
function calculate() {

a = parseInt(document.myform.myfield01.value);
b = parseInt(document.myform.myfield02.value);
c = parseInt(document.myform.myfield03.value);
d = parseInt(document.myform.myfield04.value);

z = Math.round((a + b + c + d)*100)/100;
document.myform.total.value = z;
}
</SCRIPT>

I'm not sure what you actually want to pass to the function, but you have
some alternatives. I suppose I'd probably pass references to the form
elements to be totalled to the function, along with a reference to
element which will eventually contain the total:

<script type="text/javascript">
function calculate() {
var total = 0;

for (var i = 1; i < arguments.length; i++) {
total += parseInt(arguments.value, 10);
}

arguments[0].value = total;
}
</script>
<form name="myForm">
<input type="text" name="field01" value="1">
<input type="text" name="field02" value="2">
<input type="text" name="field03" value="3">
<input type="text" name="field04" value="4">
<input type="text" name="total" value="0">
<input type="button" value="Calculate"
onclick="calculate(this.form.total, this.form.field01, this.form.field03,
this.form.field04);">
</form>

You could also pass a reference to the form and the names of the fields:

function calculate() {
var total = 0;
var theForm = arguments[0];
var theResult = arguments[1];

for (var i = 2; i < arguments.length; i++) {
total += parseInt(theForm.elements[arguments].value, 10);
}

theForm.elements[theResult].value = total;
}

and it could be called with:

<input type="button" value="Calculate" onclick="calculate(this.form,
'total', 'field01', 'field03', 'field04');">

Which specific implementation you choose depends on your requirements.

--
| Grant Wagner <[email protected]>

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