Some basic basic stuff

[Eugene Hourany]

Hi all,

I'm tearing my hair out trying to figure out why I keep getting a "element is null" error. Here's what my code looks like:

$('firstname').hide();

and I have

<input id="firstname" name="firstname" value="" />

and I get

Error: $("firstname") is null
Source File: file:///C:/Documents%20and%20Settings/142253/Desktop/test/index.html#
Line: 14

I'm doing this locally from my desktop. I'm using prototype 1.6.1.

I also would like to know how to open a json file for reading and parse it.

Thanks!

Eugene

[T.J. Crowder]

Hi,

It sounds like you're not succeeding in loading Prototype or something
else you're loading is conflicting with it, I suggest checking your
script tags. The code you've quoted and the HTML you've quoted should
work, provided Prototype is getting loaded.

FWIW,
--
T.J. Crowder
Independent Software Consultant
tj / crowder software / com
www.crowdersoftware.com

[bill]

Eugene Hourany wrote:

Hi all,

I'm tearing my hair out trying to figure out why I keep getting a "element is null" error. Here's what my code looks like:

$('firstname').hide();

and I have

<input id="firstname" name="firstname" value="" />

and I get

Error: $("firstname") is null
Source File: file:///C:/Documents%20and%20Settings/142253/Desktop/test/index.html#
Line: 14

I'm doing this locally from my desktop. I'm using prototype 1.6.1.

do you have the input declaration before the execution of the "$('firstname').hide();"

If you execute the js before the input is declared, the id will not exist.

bill

-- 
Bill Drescher
william {at} TechServSys {dot} com

[kstubs]

Try naming the ID attribute different than the NAME attribute.

[Eugene Hourany]

I never put in a name attribute, that could be part of the problem.

I solved it by putting it in a function that's called by onclick, and it worked. I was able to reference it the old fashioned JS way, and prototype's way.

Now all I want to know is how to load and parse a JSON file using the same method.

Thanks!

Eugene

[Alex McAuley]

Its happening because (as someone pointed out in a previous reply) the DOM node does not exist yet .....

 

you need to wrap the code in observers...

 

for example...

 

Event.observe(window,'load',function() {

 

    $('TheElementToHideObserver').observe('click',function() {

    $('firstname').hide();

 

 

});

});

 

//Then your html

 

 

<input type="submit" id="TheElementToHideObserver" value="Hide First Name" />

<hr />

<input type="text" name="firstname" id="firstname" />

 

 

....

 

Simple as that

 

HTH

 

 

Alex Mcauley
http://www.thevacancymarket.com

[ColinFine]

On Nov 7, 9:45 pm, kstubs <kst...@gmail.com> wrote:
> Try naming the ID attribute different than the NAME attribute.
>

What difference would that make?

However, what I was going to suggest was checking that your id
'firstname' is unique in the page. Names can be duplicated, but id's
can't.

[ColinFine]

On Nov 9, 7:04 am, Eugene Hourany <ehour...@gmail.com> wrote:
> I never put in a name attribute, that could be part of the problem.
>

No.

>
> Now all I want to know is how to load and parse a JSON file using the same
> method.

What's a JSON file?

JSON is a text representation of data which is pretty well identical
to Javascript's own notation, so you can parse it with eval().
However, if the JSON is coming from Ajax, it's already available to
you as a parsed object: see http://www.prototypejs.org/api/ajax/response