document.getElementById isn't working

[risk32]

Hi all. I'm not exactly sure what I'm doing wrong, but when I try to use the document.getEle mentById() method, it's not working. Here's what I have:

var username = document.getElementById('username')

function test()
	{
		document.write(username)
	}

...

Username: <input type="text" id="username">
<input type="button" value="test" onClick="test();">

(I am aware that I don't use braces in standard format, it just helps me keep track of what I'm doing)

When I click the button, the only thing it returns is null. Am I doing something wrong?

[Dormilich]

yes and no. if you call getElementById( ) before the document tree is finished (resp. the element in questions is attached to the DOM) you get null as result.

[risk32]

yes and no. if you call getElementById( ) before the document tree is finished (resp. the element in questions is attached to the DOM) you get null as result.

Where would be the appropiate location for the document.getEle mentById() method?

[risk32]

I actually feel like an idiot. Even though the variable was assigned globally, it didn't read inside the function. So, I put it inside the function and added .value to the end for the alert. It's working. Now to figure out arrays...