I have been experiencing a similiar behavior in 2004. Somtimes the eval() works other time it does not. In 2004 they recommend using the _root[] notation but I am having similiar results. If anyone has a consistent working solution to evaluating a full expression I would love to know it

Same goes for me, eval function sometimes works sometimes does not in professional 2004. Does anyone have any other solution ... I thought I could depend on this function .. I thought wrong.

I'm having troubles with eval and this also. I've tried using actual examples out of the docs and they don't work either. I think there is something seriously wrong with MX 2004. It's very frustrating; I can't think of a cludge.

Hey guys, I think I've figured it out.

I tried a few tests. The first thing I did was this:

var TextField1;
this["TextField1"] = 12;
trace ("TextField1 = " + TextField1);

TextField1 traced to equallying to 12. excellent. That's what I wanted. Then I tried this:

function testthis() {
var TextField1;
this["TextField1"] = 12;
trace ("TextField1 = " + TextField1);
}
testthis();

TextField1 traced to "undefined". Crap. That's no good. Then I tried this:

var TextField2;
function testthis2() {
this["TextField2"] = 12;
trace ("TextField2 = " + TextField2);
}
testthis2();

This worked! Note the variable declaration is OUTSIDE the function that I use the variable in? It seems as if that's want needs to happen. Hope that helps.

Jonathan:

I'm not sure what you mean to say. Are you telling me that the issue I was having (in the second example) was a scope problem (on my part)? I don't think so. I declare the variable in the function, before I use it in the same function. That should work.

Well, sadly this is the expected behaviour. I quote below some lines of the Macromedia Flash MX Professional documentation:

"Some of the differences between ActionScript and JavaScript are described in the following list:

ActionScript does not support browser-specific objects such as Document, Window, and Anchor.
ActionScript does not completely support all the JavaScript built-in objects.
ActionScript does not support some JavaScript syntax constructs, such as statement labels.
In ActionScript, the eval() function can perform only variable references. " (...)

That is: You can use eval to obtain variables, but not to compute anything

http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=tn_16187

Isn't it lovely :D

Jonathan,i tried to execute a ActionScript code as string format.
How to do it?

example:

var str="var t=0;t++;tarce(t);";

eval(str);//it's wrong!

Please tell me.thank you!

Ah,it isn't answer my question.it just return a value,but i need to execute the string-code.
The effect just like the eval() function in javascript.

_root["stage"]["height"] += 5;

If you want full (JavaScript type) functionality of the eval function in ActionScript 3, use the ExternalInterface class to call a javascript function in the html wrapper, thus:

Actionscript code:

...
if(ExternalInterface.available) {
   num1 = String(ExternalInterface.call("parseStr", Answer.text));
   Answer.text = num1;
}
else {
   Answer.text = "Function Unknown";
}

//...and the javascript to add to the html wrapper:

  function parseStr(str)
  {
     var result = eval(str);
     return(result);
  }
//-->

Note that in my implementation, the javascript in the container html file is in its own <script...> block. Also, my implentation assumes AS3, and was tested in Flex 2.