Page Comparison

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The rule would be written as:

for (var i = 0; i < S.value.length; i++) { 
  if (Q[i].value > 0) {
    S[i].value = Q[i].value * P[i].value; 
  } else { 
    S[i].value = 0; 
  } 
}

This rule will automatically fire whenever the user enters a value in the quantity field for any item. It will compute the subtotal for each item, for which the quantity is greater than 0 and fill in the subtotal field for that item with the computed value. If a particular item does not have a quantity, the subtotal is not computed.

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