Something like this might help you - in this example, the position of value 7 is returned:
private var _testArray:Array = new Array(5, 6, 7, 8, 9, 8, 7, 6); public function ArrayTest() { trace (_testArray.indexOf(7));
therefore for your needs:
item variableToLookFor = 9
This will return -1 if your element does not exist, otherwise it will output a position in the array.
If you need more information, you can check here for an article on AS3 arrays.
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