The JavaScript Array Object has the built-in reverse() method, which can be implemented like so:
ARRAY_NAME.reverse()
Simple enough, right? Well, I'm bewildered as to how to do this with my own methods. For example, let's assume I've got a function called changeColor, and I wanted to attach it to an element like so:
document.getElementById('someElement').changeColor('red');
How would I go about doing that?
whizard
12-17-2006, 02:32 AM
I think what you're talking about are event handlers.. I'm not exactly a JS whiz, but hopefully this link will help, if not, my bad!
http://developer.mozilla.org/en/docs/DOM:element.addEventListener
Dan
Sorry, way off. I'm almost certain it can be done (attaching functions, that is) using JavaScript Objects, I just can't seem to piece it together. It could just as easily be done with this function:
function changeColor(element, color)
{
element.style.color = color;
}
but I'm a stickler for knowing how to do things, and I've always pondered the possibility of attaching functions. There are several native functions that act via attachment (the ARRAY.reverse() that I mentioned previously is a perfect example), so it must be possible.
koyama
12-17-2006, 02:42 AM
... or do you mean assigning your own methods? Perhaps this example will help you.
<html>
<head>
<title>test</title>
<script type="text/javascript">
function setColor(myColor) {
this.style.color = myColor;
}
</script>
</head>
<body>
<span id="monkey">hello</span>
<input type="button" value="go" onclick="document.getElementById('monkey').changeColor('red')" />
<script type="text/javascript">
document.getElementById('monkey').changeColor = setColor;
</script>
</body>
</html>
So very close. In order for that approach to work, however, I'd have to do
document.getElementById('ELEMENT_IN_QUESTION').changeColor = setColor;
for every single element I'd like it to work with, though. Not exactly efficient. Is this the only way to do it, though?
So very close. In order for that approach to work, however, I'd have to do
document.getElementById('ELEMENT_IN_QUESTION').changeColor = setColor;
for every single element I'd like it to work with, though. Not exactly efficient. Is this the only way to do it, though?
HTMLElement.prototype.changeColor = setColor;
In Firefox and Opera, at least.
Works to perfection. Much thanks to both of you.
