Help with Javascript in JSP page

Question

I have a JSP which gets a value called sum from the DB...

String sum= request.getAttribute("s").toString();
int s = Integer.parseInt(sum);

I have a field in a form called weight who's value cannot exceed sum.

So on clicking submit i'm running a function called validate. Which would check if field is greater than or equal to sum but it keeps giving me the warning all the time.

<script type="text/javascript">
function validate()
{
    var x= document.getElementById("s");
    if(document.getElementById("weight").value>x)
    {
        alert("Weight exceeds maximum limit...!!!");
        return false;
    }
    return true;
}   
</script>

Would appreciate the help..

Answer 1

This has nothing to do with JSP. You need to parse the values into numbers using parseInt() or parseFloat() before comparing. This is because the .value attribute is always a string. You are also comparing an element's value with an element, which does not make sense.

Try this:

function validate()
{
    var weight = parseFloat(document.getElementById("weight").value),
        maxWeight = parseInt(document.getElementById("s").value, 10);
    if(weight > maxWeight)
    {
        alert("Weight exceeds maximum limit...!!!");
        return false;
    }
    return true;
} 

Answer 2

s is a Java variable so you cannot reference it through document .

Try something like:

var x = <%=Integer.parseInt(sum); %>
if (document.getElem...