变量的AS3对象表示法

Question

I have some variables in the format:

var like6Y:Number = 50;

Later I am dynamically setting some:

num=6;

Then I am trying to use that num to get the variable like6Y:

 like+6+Y

I know that is totally wrong but I seem to remember you could use some kind of object notation to accomplish this:

["like"+num+"Y"] 

Or something along those lines. But I can't remember how to do it. Thanks

Answer 1

It can be done - just access this["like"+num+"Y"] . Assuming like6num is a property of the current object, otherwise just change this to the object's name.

Answer 2

Even though something like this["like" + num + "Y"] would work for global variables, the datatypes Array and Vector (use Vector if you know all values will be of the same type and that every index of it's length will be assigned a value) are built for the task of accessing a value by an integer reference. They also provide the added benefit of giving you greater control of the scope in which the variables are placed.

For instance:

var likeY:Array = [-10, 0, 10, 20, 30, 40, 50];
var num:int = 6;
trace(likeY[num]); //prints 50

Answer 3

in Javascript you can use window["like"+num+"Y"] or eval("like"+num+"Y") ... but there is no alternative in AS3.

Also this["like"+num+"Y"] work if you are trying to access a public *property of the current class.

But there are some third party libs which brings the eval method to AS3. I never used it, but you can try, [Eval in AS3: Tips for Executing Dynamic Actionscript][1] http://danielmclaren.com/node/113