Constant Sum error message math

Question

I have a client who is asking if we can have the error message show the remaining difference, basically:

[%ErrTotal()%] <minus> [%ErrCurSum()%]

Can the error messages interact with math operators?

Thanks.

Answer 1

Via custom JavaScript verification:

$(document).ready(function(){
    var total = 100;
    var sum = $('#ConstantSumQ_div .question_body tbody tbody > tr:last-child input').val();
    var remaining = total - sum;
    if (remaining > 0)
    {
        strErrorMessage = 'You need ' + remaining + ' more.';
    }
})

You will need to set the custom JavaScript verification to run before the system JavaScript verification, rather than after.