See my thread (third post):

An array of arrays of of radio buttons

It's essentially the same thing.

Give both checkboxes the same name, both hidsum boxes the same name, and both sum boxes the same name. Then use Javascript as follows:

JavaScript / DHTML / AJAX Syntax (Toggle Plain Text)

function add()
  var i, d, e;
  e = 0;
  for(i=0;i<2;i++){
    if(document.form1.status[i].checked) document.form1.hidsum[i].value=0
    else document.form1.hidsum[i]1.value=document.form1.sum[i].value;
    a=document.form1.hidsum[i].value;
    e = e + parseInt(a);
  };
  document.form1.total.value=e;
};

function add() var i, d, e; e = 0; for(i=0;i<2;i++){ if(document.form1.status[i].checked) document.form1.hidsum[i].value=0 else document.form1.hidsum[i]1.value=document.form1.sum[i].value; a=document.form1.hidsum[i].value; e = e + parseInt(a); }; document.form1.total.value=e; };

Notice that array indexes begin with 0, not 1.

JavaScript always counts from 0 on arrays and object lists.

"'document.form1.status' is null or not an object"

This indicates that you forgot to change the names in the html to match the change in the JavaScript. You were supposed to rename your html objects so they have the same name "status" instead of having the names "status1" and "status2".

You have a bug. There must never be a semicolon before an else statement.

If the value of document.form1.sum.length is zero, the loop will never execute. The termination condition is met when the loop is entered.

If there is only one input box, why are you bothering to find the sum?