phpeveryday.com

if we want to write:

array(0=>'a', 1=>'b', 2=>'c', 3=>1, 4=>2, 5=>true)

We can use:

<array length='6'>
  <string>a</string>
  <string>b</string>
  <string>c</string>
  <number>1</number>
  <number>2</number>
  <boolean>true</boolean>
</array>

This is example using:

<wddxPacket version='1.0'>
  <header />
  <data>
    <array length='4'>
	  <number>1</number>
	  <string>Wiwit Siswoutomo</string>
	  <string>PHPEveryday.com</string>	  
	  <boolean>1</boolean>	  
    </array>
  </data>
</wddxPacket>

The important note: this is zero based arrays. Creating arrays that are not zero-based, such as array(2=>'c',3=>'d'), would result in a struct with named variables rather than array elements.