Shortcut to assigning instance names?

[5Five555]

If you have those 16 buttons already added on the stage, I'll assume the parent of the buttons is the stage, you can do

for (var i = 0; i < 16; i++) {
    var btt:* = stage.getChildAt (i);
    var string:String = "btn_" + i;
    btt.name = string;
} 

That'll only work if the first 16 children of your stage are the buttons. But you can set their instance names using the .name property in AS3.