getElementsByTagName help

[makingphpwork]

Hello all,

Just wanted some help with getElementsByTagName function

Say for a XML

<root>
<aaa id="a">
<a id='1'>
<field1>
<field2>
</a1>
<a id="2">
<field1>
<field2>
</a2>
</aaa>

<aaa id="b">
<a id ="1">
<field1>
<field2>
</b1>
<a id ="2">
<field1>
<field2>
</b2>
</aaa>
</root>

If I need to get all element tag<field1> from the second <aaa> , I tried following

$params = $dom->getElementsByTagName("//root/aaa[2]/a/field1");

also i tried using
$params = $dom->lastChild->getElementsByTagName('field1');

but neither works...

Any suggestions...

Thanks in advance
Regards

[harmor]

I'm infamiliar with DOM too but try

document.getElementById('field1')