[thelist] javascript comparison

Jason Handby jasonh at corestar.co.uk
Wed Oct 29 12:50:08 CST 2003

Hi Rob,

> My javascript test is testing supposedly numerical values as strings, when
> they should be compared by actual value.


> Is there a way I can cast values in javascript?

You can use the parseInt() function to convert them to integers:

	if (parseInt(bid.previousbid.value) > parseInt(bid.nextbid.value) )
		alert("Please enter a bid greater than $" + bid.previousbid.value + ".");
		  return false;
		return true;

You should also check to make sure they actually *are* integers. If
parseInt() can't convert them to integers for any reason it returns a
constant called NaN (= Not a Number), so you should also check for that
somewhere in your form validation function, e.g.:

	if (parseInt(bid.previousbid.value) == NaN || parseInt(bid.nextbid.value)
== NaN)
		return false;

(If you decide you want to allow non-integer amounts (dollars and cents) you
might want to use parseFloat() instead.)



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