We commonly want to send an Array object from AS to PHP – while there are perfectly good, robust options available (AMFPHP, Serializer, etc), and obviously you could convert the Array to a string and explode it in PHP, that can be impractical if dealing with non-trusty data (like user input), since the delimiter might appear within any particular element’s value.

here’s a quick-and-dirty-and-hacky trick I’m ashamed to admit I’ve used a couple times. Note that this would only ever work on a single array.

[as3]var array:Array = ["bob", "ken", "jim"];

var request:URLRequest = new URLRequest("some-script.php");
request.method = "POST";

var variables:URLVariables = new URLVariables();

for(var i:int = 0; i < array.length; i++){
variables[i] = array[i];

request.data = variables;

var loader:URLLoader = new URLLoader();