how to use loop for array - php

Question

I have a array which it reads its cells from a xml file,i wrote it by "for" but now because i don't know how many node i have i wanna to write this loop in a way that it start and finish up to end of xml file.my code with for is:
$description=array();
for($i=0;$i<2;$i++)
{
$description[$i]=read_xml_node("dscription",$i);
}
and my xml file:
<eth0>
<description>WAN</description>
</eth0>
<eth1>
<description>LAN</description>
</eth1>
in this code i must know "2",but i wanna to know a way that doesn't need to know "2".

Answer 1

i am not sure what kind of parser you are using, but it is very easy with simplexml, so i put together some sample code using simplexml.
something like this should do the trick:
$xmlstr = <<<XML
<?xml version='1.0' standalone='yes'?>
<node>
<eth0>
<description>WAN</description>
</eth0>
<eth1>
<description>LAN</description>
</eth1>
</node>
XML;
$xml = new SimpleXMLElement($xmlstr);
foreach ($xml as $xmlnode) {
foreach ($xmlnode as $description) {
echo $description . " ";
}
}
output:
WAN LAN

Answer 2

$length = count($description);
for ($i = 0; $i < $length; $i++) {
print $description[$i];
}

Answer 3

The parser you use might allow you to use a while loop which will return false when it has reached the end of the XML document. For example:
while ($node = $xml->read_next_node($mydoc)) {
//Do whatever...
}
If none exists, you can try using count() as the second parameter of your for loop. It returns the length of an array you specify. For example:
for ($i = 0; $i < count($myarray); $i++) {
//Do whatever...
}