Performing Arithmetic Calculation In Selectboxs Using Javascript

Question

I have a case something like this:

How can I do when choose example A = 3 and B = 5, will update 8 in column C automatically, and so on for different column and rows ?

The help will be very appreciated. Thank you in advanced !

Answer 1

Try this:

1. Call the select boxes like "a1", "a2", "b1", "b2"

2. Call the cells in C like "c1", "c2"

3. Make the onchange event of the select boxes be like this:

   function update() {
       var id = this.id.substring(1);
       var value1 = parseInt(document.getElementById("a" + id).value);
       var value2 = parseInt(document.getElementById("b" + id).value);
       document.getElementById("c" + id).innerHTML = value1 + value2;
   }