Checking Index Number of an Item in an Array

programming flash
1

I have this Array


var shoprubriken:Array = new Array();
shoprubriken[0] = "43"; 
shoprubriken[1] = "44"; 
shoprubriken[2] = "45"; 
shoprubriken[3] = "46"; 
shoprubriken[4] = "47";
shoprubriken[5] = "48"; 
shoprubriken[6] = "49";
shoprubriken[7] = "50";
shoprubriken[8] = "51";

Now I wanted to check on which Index Position maybe the 47 is

How can I archive this on a Button or Function???

any hints??

thanx in advance

ChromeD