# This\[\] gives Error 1056: Cannot create property

**URL:** <https://forum.kirupa.com/t/this-gives-error-1056-cannot-create-property/273283>\
**Category:** flash\
**Created:** [October 13, 2008, 11:43pm UTC](https://forum.kirupa.com/t/this-gives-error-1056-cannot-create-property/273283 "2008-10-13T23:43:55Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![cauchy](https://avatars.discourse-cdn.com/v4/letter/c/a88e57/32.png) [@cauchy](https://forum.kirupa.com/u/cauchy)\
**Post date:** [October 13, 2008, 11:43pm UTC](https://forum.kirupa.com/t/this-gives-error-1056-cannot-create-property/273283/1 "2008-10-13T23:43:55Z")

</div>

If I create a simple fla and class file, where the fla has one line:

var myTest:Test = new Test();

and the class file has:

package  
{  
import flash.display.Sprite;

```
public class Test extends Sprite
{        

    public function Test() 
    {
        this["ab"] = "stri";
        trace(this["ab"]);            
    }
}

```

}

is gives the 1056 error. Now this is a simplistic example, but I need to use dynamic variable names. What is disturbing is that in my actual code, before I made some seemingly unrelated changes, using the this[] word worked perfectly fine. Are there some conditions that would make this stop working suddenly? I was a little surprised to replicate the error in this simple example, so I can’t understand how it ever seemed to work in the first place in my real code