javascript getelemenetbyname and value

ted_chou12 · 01-29-2013, 07:01 PM

Hi, I know this is a linux forum, but there are probably experts on js too:

Code:

<!DOCTYPE html>
<html>
<head>
<script>
function getElements()
{
document.getElementsByName("x").value="asshole";
alert(x.length);
}
</script>
</head>
<body>

<input name="x" type="button" value="shit">
<input name="x" type="button" value="fuck">

<input type="button" onclick="getElements()" value="How many elements named 'x'?">

</body>
</html>

sorry for my keywords, those are my foos and bars when i code
For the above code, the length returns correctly, but it doesnt chave the button values for me, why is that?
Thanks,
Ted

mina86 · 01-30-2013, 06:47 AM

Quote:

Originally Posted by ted_chou12

sorry for my keywords, those are my foos and bars when i code

You clearly copied the code from W3Schools, yet you bothered to change place-holders?

Quote:

Originally Posted by ted_chou12

For the above code, the length returns correctly,

I doubt that since you have no variable named x.

Quote:

Originally Posted by ted_chou12

but it doesnt chave the button values for me, why is that?

Because you are accessing a non-existent property “value” of whatever getElementsByName returns, which is kind of array. What do you want to happen after you click the button exactly?

ted_chou12 · 01-30-2013, 01:02 PM

Quote:

Originally Posted by mina86

You clearly copied the code from W3Schools, yet you bothered to change place-holders?

Yes, this is a modified example from w3schools, but since I am only demostrating my idea, so I thought the source of the code doesnt matter, as long as it shows what I wanted. I did remove the orginal radio buttons and added input buttons instead if you see it in the code.

Quote:

I doubt that since you have no variable named x.

The shit and fxxx buttons are named x, isn't that sufficient? cause I read it that id can only have one on each page, while name can be multiple.

Quote:

Because you are accessing a non-existent property “value” of whatever getElementsByName returns, which is kind of array. What do you want to happen after you click the button exactly?

I want to see both of the buttons change their values. This could be done with ID, but then I would have to give them separate names. I was thinking what if I want something more elegant?

Btw, you can check it on this page, just copy and paste it, the length does return correctly.
http://www.w3schools.com/jsref/tryit...getelementbyid

Thanks,
TEd

mina86 · 01-31-2013, 07:05 AM

Quote:

Originally Posted by ted_chou12

The shit and fxxx buttons are named x, isn't that sufficient? cause I read it that id can only have one on each page, while name can be multiple.

You do not declare a JavaScript variable though. The name of the elements do not matter.

Quote:

Originally Posted by ted_chou12

I want to see both of the buttons change their values. This could be done with ID, but then I would have to give them separate names. I was thinking what if I want something more elegant?

You need to iterate over the array-like object that getElementsByName() returned.