[Phpwm] [OT] Any ideas how to do this?

[Ian Munday]

----
Ian Munday
Illumen Ltd.
www.illumen.co.uk

T:  +44 (0)121 703 3111  /  +44 (0)845 00 999 00
E:  ian.munday at illumen.co.uk



On 25 May 2006, at 20:22, Phil Beynon wrote:

>>> I have two text boxes within a form and a radio button.
>>> There is a ratio between the values of the starting values within  
>>> the
>>> text
>>> boxes, which is actually the aspect ratio of an image. The  
>>> function of
>>> the
>>> radio button is to say overide the aspect ratio.
>>>
>>> If the radio button isn't set and one of the text box values is
>> altered I
>>> want the value of the second box to alter to the same (interger  
>>> value)
>>> ratio. If the radio button is set I dont want the value of the  
>>> second
>>> box to
>>> alter.
>> Hi,
>>
>> Some code for you at:
>> http://www.phpwm.org/pastebin/index.php?id=49
>>
>> It assumes the text-areas have values in them to start with, and
>> initially
>> this is the ratio used for further changes.
>> If you change one value with the checkbox unticked, then the ratio is
>> recalculated, so upon re-ticking it, this new ratio is used for
>> calculations (experiment and see if that doesn't make sense...).
>>
>> As one of the comments mentions, if this is going in anything
>> larger than
>> <something very small>, then using window.onload directly is
>> probably not
>> a good idea.
>>
>> Greg Jones
>>
>
> Cheers Greg,
> That's actually very near what I wanted indeed. Is there a way of  
> making it work both ways text1 -> text2 as now and also text2 ->  
> text1 onchange?
>
> Couple of oddities on it though that I noticed -
> On the default starting value of 300/200 if you put a leading zero  
> in front of the 300 then the 200 drops to 128 for some reason.
>
> If there is no content in text1 text2 says "NaN" for some reason!

NaN is a special value representing 'Not a Number'.  It will be  
returned because you are attempting a numeric calculation on a non- 
existent value (or an empty string) in text1.  Suggest you either  
perform some input validation, or handle this error in some other way.

Ian