I am having trouble with the following function. I am trying to change the
ID of a hidden form object inside a table row. I have used alert() to test
where it breaks and it seems to be on the last line of the function where I
am trying to place the new text back into the table row. Anyone any ideas
where I'm going wrong as I'm not a great Javascript coder. Or even if you
know a better way to carry out what I am trying to do.

Thanks in advance.

this.onDrop = function(table, droppedRow) {
     var rows = table.tBodies[0].rows;
     var rowsCount = parseInt(rows.length);

     for (var x = 0; x <= rowsCount - 1; x++)
     {
         //Get string contents of row
          var curRowString = rows[x].innerHTML;

         //Find where ID tag is
          var IDStart = curRowString.indexOf("ID");

         //Find > immediately after ID tag
          var IDEnd = curRowString.indexOf(">", IDStart);

         //Get ID value
          var IDVal = curRowString.substring(IDStart+5,IDEnd)

         //Replace old ID with new ID
          var oldID = "ID" + IDVal;
          var newID = "ID" + (x+1);
          var newRowString = curRowString.replace(oldID, newID);

          //*********** Crashes on line below ***************
          rows[x].innerHTML = newRowString;
     }
}