Loops and onError when file doesn't exist

[Fingerprint]

I've got a directory of files with double digit numeric names, and I want to loop through them all to add into a databinding object, but they're not sequential numbers (the file name is generated randomly).
I've been trying to make it ignore the error and move to the next number, but I keep getting 'System cannot find specified resource'.
I've never used the onError event handler before - so does anyone have any tips?
Here is my code:

function addData()
 {
 for (var i=50;i<100;i++)
  {
  var added = &quot;&quot;;
  added = i;
  added += &quot;.csv&quot;;
  added.onError = i++;
  document.tdcInfo.dataURL = &quot;&quot;;
  document.tdcInfo.dataURL = added;
  document.tdcInfo.reset();
  }
 }

Thanks for any help,

- fingerprint