Continuous updating

[offler]

Hi,

is it possible to get the following with javascript:
Mark checkbox 1, read the value and print out the value.
Mark checkbox 2, read the value, add them to the value from checkbox 1 and print the new sum out.
Unmark checkbox 1 ... and alter the sum.

(It is a lookalike for a shopping car but without submit-buttons!)

Thx a lot,
offler

[dcrombie]

I would approach this in two steps:

1) write a function that reads the form, calculates the the total and updates a text field;

function sumForm(form) 
{ 
 if(form.checkbox1.checked) ...; 
 if(form.checkbox2.checked) ...; 
... 
 form.total.value = ...; 
}

2) add event handlers to the checkboxes;

<input type="checkbox" name="checkbox1" ... onClick="sumForm(this.form)" ...> 
<input type="checkbox" name="checkbox2" ... onClick="sumForm(this.form)" ...> 
<input type="text" name="total">

;)