Bring old javascript up to date

[LDJB81]

A colleague of mine has an old 8.1 report which he wants to migrate but there is a piece of java code which needs to be updated. Can anybody help bring this code below up to date?

<script language="javascript">

if (document.forms["formWarpRequest"].elements["_oLstChoicesMARCHE1"].length ==1)
{
document.forms["formWarpRequest"].elements["_oLstChoicesMARCHE1"].selectedIndex = 0;
document.forms["formWarpRequest"].elements["_oLstChoicesDATE1"].selectedIndex = 0;
setTimeout('listBoxMARCHE1.autoSubmit()', 100);
}
</script>