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traditional event model - puzzled


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Hi Guys

 

I have been a jquery junky for a bit too long and neglected much of the raw javascript behind it...hence this simple question.

 

When I try to register an event in the format of :

element.onclick = funcName;

the only way I can get this to work is with:

document.getElementById('elementId').onclick = myFunc;

Whereas if I try and give this event a handle (below) it doesn't work at all and I get an 'undefined' error in console even though it plainly is defined. But surely these two statements amount to exactly the same thing? 

var someElement = document.getElementById('elementId');

someElement.onclick = myFunc;   // This doesn't work

So what am i missing?

 

Thanks,

 

Drongo

Edited by Drongo_III
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https://forums.phpfreaks.com/topic/278250-traditional-event-model-puzzled/
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This should work.

http://jsfiddle.net/6eJuB/

 

window.document.querySelector("#elmId").addEventListener("click", myFunc, false);

 

 

Thanks for that. But it wasn;t so much that I couldnt get the event to work, or that I couldn't register the event in another way. What I was driving at is to try and understand why it works with document.getElementById but not when I simply use a resource (i.e. set a var with document.getElement... and then assign it to the event). Any ideas why that may be?

Thanks for that. But it wasn;t so much that I couldnt get the event to work, or that I couldn't register the event in another way. What I was driving at is to try and understand why it works with document.getElementById but not when I simply use a resource (i.e. set a var with document.getElement... and then assign it to the event). Any ideas why that may be?

http://jsfiddle.net/6eJuB/1/

Most likely you tried to call the getElementById before the page loads or before the element is on the page.

 

 

Perhaps you can point out where i'm doing it wrong?  The below code doesn't work. 

<!doctype html>
<html>
<head>
	
	<script type="text/javascript">
	
		var mylink;
		
		function init(){
		
			mylink = document.getElementById('link1');
			alert(mylink.id);
			myLink.onclick = myFunc;
		}
		
		function myFunc(){
		
			alert('click worked');
		}
				
	</script>

	

</head>

<body onload="init();">

	<a href="#" id="link1">Click me</a>
	
	
</body>
</html>

But if I replace that init function with a direct call to document.getElement (as per below) it works fine. So I am just trying to understand either what I am doing wrong or whether there is some fundamental precept of javascript i am missing (probable)...

 


		function init(){
		
			//mylink = document.getElementById('link1');
			//alert(mylink.id);
			document.getElementById('link1').onclick = myFunc;
		}

 

 

 

And thanks for this mate but this is a different type of event registration. I am trying to work out why the traditional model doesnt seem to work for me

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