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document.getElementById always returns null
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Millennium
Clinically Insane
Join Date: Nov 1999
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Sep 20, 2004, 06:23 AM
 
I'm having a problem using document.getElementById in Firefox and Safari: it's always returning null in any page I write, whether or not the ID actually exists in the document. This has been happenning in pages that I know are validating, so clearly I'm doing something wrong, but I can't figure out what it is.

Here's some sample code:
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>getElementById Test</title> <script type="text/javascript"> <!-- alert(document.getElementById("hello")); --> </script> </head> <body> <a href="#" id="hello">Hello</a> </body> </html>
Anyone have any ideas? I can't find anything immediately wrong with this, but if Firefox and Safari are both failing then I know there must be something I'm missing.
You are in Soviet Russia. It is dark. Grue is likely to be eaten by YOU!
     
ntt
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Join Date: Jul 2003
Location: Seattle, WA
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Sep 20, 2004, 09:08 AM
 
The script should be _after_ the id is defined. At the point the script runs, the id doesn't exist. Try putting the script before the closing body tag.
     
Millennium  (op)
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Sep 20, 2004, 10:04 AM
 
That would make sense, but it seems to be a problem even after the page is fully loaded. I can type the following into Firefox's JavaScript Console even after the page has loaded...
Code:
document.getElementById("hello")
...and it still returns null.
You are in Soviet Russia. It is dark. Grue is likely to be eaten by YOU!
     
madmacgames
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Sep 20, 2004, 11:31 AM
 
seems to work just fine if you put the JS in a function and call it when the page is done loading:

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>getElementById Test</title> <script type="text/javascript"> <!-- function doIt() { alert(document.getElementById("hello")); } --> </script> </head> <body onload="doIt();"> <a href="#" id="hello">Hello</a> </body> </html>
The only thing necessary for evil to flourish is for good men to do nothing
- Edmund Burke
     
Simon Mundy
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Join Date: Jun 2001
Location: Melbourne, Australia
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Sep 21, 2004, 01:17 PM
 
Even if you call afterwards, as ntt said:-

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>getElementById Test</title> </head> <body> <div id="hello">Hello</div> <script type="text/javascript"> <!-- alert(document.getElementById("hello")); --> </script> </body> </html>
Computer thez nohhh...
     
   
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